After the recent decision not to build the Transrapid in Munich, I did some reading on the topic and it seems that many countries in the world have considered of installing a Transrapid or some other Maglev train, but the technology has always lost. The Shanghai Transrapid is an exception, but it follows the rule in that it's planned extensions are highly debated already. It seems that there will not be a single new construction project in the next ten years and maybe not even in the next twenty years. (With the exception again, of the Chinese maybe building a short extension in Shanghai just to show the world that they now master the technology by themselves with less aid from Germany.)
So why did Maglev fail (so far)?
Well, I think it's because significantly more expensive than "classical" trains and it doesn't have as many advantages as thought.
Speed: TGV did test runs at roughly the same speed as Maglev trains. The only reason, why current high-speed trains don't go faster than 300 to 350 km/h is that energy cost becomes to high.
Power consumption: Maglev boasts it self with "zero friction movement" ignoring that at high speeds, air resistance causes most of the friction and this is exactly the same for wheel/rail as for Maglev trains. Only that the maglev train needs at lot of additional energy just to keep it afloat over it's track.
Noise: At low speeds Maglev is indeed less noisy, but at high speeds the same argument as for energy comes in: no advantage any more.
Maintenance: no friction, they say, means no wear and tear; and thus much of the system will be maintenance-free. On the other hand, however, Maglev has much more technology embedded in the tracks and is much more sensitive to fine-tuning of all it's sensors and actors. From experience in rail we know that steel rail tracks can indeed take a lot of traffic before they need to be maintained. (And when they don't get maintained, they can still take slower traffic and will give a more bumpy ride, while Maglev won't probably work at all until its 10mm gap is within required tolerance.)
Finally, also classical rail has evolved a lot since it was invented 150 years ago (maybe just 111 years for electric trains). Trains use still compatible overhead wires or third rails from 100 years ago and steam trains do still travel (for historic/touristic purposes) on tracks shared with Germany's high-speed trains, but the technology under the hood has evolved a lot: among other things power electronics allow more efficient traction and regenerative braking; locomotives are replaced with self-propelled carriages; and signalling and train control become automated just in the same way it is for Maglev trains.
The technology race is still going on and Maglev can still take over and/or find its niche... and I am sure this will happen before we reach the sci-fi epoch where everybody flies around in their cars...