The system that is sold is the Transrapid, which has a test circuit in Germany for many years now. Only recently however were there serious discussions about building commercial lines in Germany.
Plans for a fast connection between Berlin and Hamburg were scrapped. Industry wouldn't invest without more goverment support, government wouldn't invest without more industry support (or something like that). It would have been expensive (multi-billion euro investment) with questionable profit. A proposal for saving money by only building a single track connection came into play, but that's just ridiculous.
The biggest competitor is of course the airplane but also conventional trains (by being a lot cheaper for the same distance). The biggest advantage of trains in general is that you can travel from city center to city center, whereas you have to travel from center to airport to airport to center with planes. Now with a train that is as fast as a plane on the average there is some advantage for the train (speed means overall here, air space is quite busy, inducing delays on starting and landing).
The current plan for building lines in Germany is to build shorter routes, with a few alternatives being under consideration. One such is the connection Munich airport-main station, supposedly cutting down the travel times from circa 45 minutes to 20 minutes or less (including stops).