Why another Linux distribution? "Surely there are enough of them already" is the common refrain. Ubuntu Linux is a solution to a lacking niche in the Linux ideaspace -- a polished distribution aimed at novice users that is both free and community driven. If it helps to understand in terms of comparison, you can think of Ubuntu as a hybrid of the ideas of Debian and Fedora.
The new Ubuntu Linux is based on a snapshot of the Debian unstable distribution, which they take and then add packages to. They time their desktop releases to coincide with the new releases of the Gnome, updating at six month intervals. What this means is that you get Debian packages that are no more than six months old on a system base that is quite stable -- and with over 13,000 packages to choose from they have pretty much everything you could imagine.
Their first release, 4.10, based on the release date of October of 2004, is named Warty Warthog, perhaps in recognition that their initial release will have some rough edges to it. As a promotion they are shipping free CDs of Ubuntu Linux when the final release is made, so if you are interested you can check it out without having to burn your own CD.
The Ubuntu team is focused on getting things to Just Work, and the idea is that you should never have to use a command line tool to configure your system. Ubuntu uses the new Debian installer developed for the upcoming Debian Sarge release, so upon initial viewing the two look quite similar. The installer is text-based, which might be a bit of a shock to users used to Fedora, SuSE, Mandrake, or other graphical installers. Despite their similar text-based look, the Ubuntu installer is much more straightforward and simple than the Debian installer. It was shocking just how few questions Ubuntu bothered to ask and how well it worked.
The installer has a very important usability drawback: if you don't want it to take over your entire disk, you have to partition it manually. Their partition manager has no support for resizing NTFS (the default Windows 2000/XP filesystem), so you need this functionality you'll have to do that first with qtparted (on Knoppix or the System Rescue CD). Even if you don't need to resize an NTFS partition, you will have be somewhat knowledgeable and manually create a swap and root partition. The option on the Mandrake installer "use free space on Windows partition" is sorely missed here.
For a knowledgeable user who can get past the partitioning step, however, Ubuntu's installer works like a charm. It has no problem autoconfiguring most video, network, and sound devices without you having to provide any input at all - it worked perfectly on the three desktop systems I installed it on. When it doesn't automagically work, however, it can be a bit annoying as I found on my poorly supported Toshiba laptop.
After installation, the most striking thing is that Ubuntu uses the brand new Gnome 2.8. It uses a subset of the new Gnome System Tools for system management, and uses the new Evolution 2.0 - a significant improvement over Evolution 1.4. Ubuntu uses the popular Mozilla Firefox 1.0 as its default browser, and OpenOffice.org for its office suite. Overall it has to be said that the standard Ubuntu install is very Spartan and provides sane default applications for a Gnome environment.
In addition to providing Gnome 2.8, the Ubuntu team has also done some further customizations to the desktop. They have replaced the Gnome "Actions" menu with a new one, "Computer" which contains links to your Home directory, Desktop, Disks, Search for Files, and Networks amongst the usual "Actions" menu items. In addition, they use a Trashcan applet instead of having trash on the desktop. This means that by default the desktop is completely blank, which is quite interesting and unique.
Ubuntu uses a variation on the popular new "Industrial" Gnome theme developed by Novell. It uses a brown colour scheme that is very unusual, but it works better than it might sound. The Ubuntu artwork currently shipping is apparently not finalized yet, so what we see in the preview may not be what ships with their initial release in October.
The preview distribution being shipped right now by Ubuntu is desktop-oriented, and one nice feature is that no ports are open and listening by default. This is brilliant, because with no open ports the OS is very secure. I have to admit that the lack of OpenSSH in the default install surprised me, but it was easy to install in the Package manager.
In addition to the obvious, Ubuntu does a lot of nice things that might not be apparent on the first use. One of those things is their integration of Project Utopia (hal, d-bus, udev) into the Operating System. When I insert a flash card into either my USB or PCMCIA card reader, Ubuntu mounts it and puts a little icon on my desktop for easy browsing... very slick, something I've not seen yet on Linux.
Perhaps the most striking aspect that sets Ubuntu apart from other Linux distributions is how they handle the root (system administrator) account. By default, the root account is disabled, and the system relies heavily on sudo to perform administrative tasks. This means to edit a system file you use "sudo vim filename", and are then prompted for your user password, and if you want a root terminal you use "sudo -s". All of the GUI system administration tools in the menu use sudo as well, so you'd never need a root password to maintain Ubuntu.
Ubuntu gives users the choice between two methods of installing new software packages, either using the friendly GUI of Synaptic Package Manager or the power of the command-line apt tools. There are three major repositories of software for Ubuntu: "main", "restricted", and "universe". The main repository contains the packages officially supported and maintained by the Ubuntu developers, and contain most of what you'd need for a Gnome desktop environment, such as Abiword, Epiphany, and Inkscape. The restricted repository contains binary drivers like NVIDIA and ATI which are not open source and not fully supported, but included for those who need them to get their hardware to work.
In addition to the programs officially supported by the Ubuntu developers, you can choose additional software from the "universe" component. Universe is a collection of software from the huge and diverse Debian "unstable" package repository, frozen at the time of the latest Ubuntu snapshot. If the Debian packages were working at that time, they will run on your Ubuntu machine flawlessly. These are not officially supported however, so if something breaks or there are needed security updates you are own your own for fixing them.
Like many other Open Source projects Ubuntu maintains a Bugzilla to track and manage bugs. But unlike most Bugzilla's, the Ubuntu team seem to actually pay attention to them. I noticed that my PCMCIA compactflash reader didn't automount when I inserted it into the slot, as it did with the USB card reader. After I filed this bug, the developers paid attention to the problem and fixed in within days - it was impressive that something that has never worked for me before on Linux could be considered a bug and fixed so promptly.
You can get support for Ubuntu on the mailing lists, IRC channel, and soon they will have web forums. In addition, Canonical, the company that employs many of the Ubuntu developers, plans to offer commercial support for Ubuntu.
Room for improvement:
Ubuntu Linux is still a very new distribution, and has some areas that it could stand to improve. The installation is a little bit too automatic, it would be nice if they would autoconfigure your video card and then show you a test - and if it fails to autoconfigure it could prompt you to set it up properly. This concept could be applied to a few other areas too in the installation. Another rough area is the boot process, where you get an old-fashioned text output of the boot process unlike what users might be used to from SuSE, Mandrake, or Red Hat - though this is promised to be fixed for the next release.
Another area that might be an issue for some is the lack of supported KDE packages in Ubuntu. These packages are available in the "universe" component but are unsupported and not integrated into the desktop. If you can't live on Linux without solid KDE packages, Ubuntu is probably not the distribution for you. The developers have made some vague promises of things to come regarding KDE, but at this time only Gnome is recommended on Ubuntu.
Laptop support is still sub par, an area that the Ubuntu team plans to focus on for the future. But in the meantime, switching between various different wireless networks is a difficult task. It is a shame that neither Novell's netapplet nor Red Hat's NetworkManager made it into the first release of Ubuntu. Suspend and hibernate functionality is also quite limited, and depends on the make and model of your laptop.
Another notable drawback to Ubuntu is the lack of X.Org packages, something most every distribution has in recent times. They do use a heavily patched XFree86 4.3.0 xserver and have backported many of the new drivers to their older version of XFree, but it's still not the same. Again, they have promised this to be fixed on their next release - I'm sure you notice the pattern by now, and the reason why this release is nicknamed the Warty Warthog. It's very good, but not quite perfect yet.
With a six-month release schedule, solid funding, and many prominent Debian and Gnome developers employed by Canonical to work on Ubuntu, the future looks bright for this project. For such a new distribution they have already come quite a long way. The mailing lists and IRC channel are full of people checking out the distribution, and has already moved into the top twenty distributions listed on DistroWatch, an impressive feat considering how young the project still is.
As Ubuntu Warty is still in preview period, there are several quirks that are still being ironed out before the final release, but it is already a very stable and solid desktop system. I predict that this distribution will have the staying power that so many other Linux options seem to lack.