"The wear and tear increases are just too expensive" presumably refers to ballasted track.
Perhaps if and when concrete slab track becomes economically cheaper, this might change.
No it doesn't, since the Japanese and now the Chinese have both concluded that 360kph running is not viable, and both networks extensively use slab track already.
(The shinkansen is almost entirely slab track as far as I can tell).
The primary wear appears to be on things like the OLE and on the train itself.
The Germans seem to use it rather a lot...
If the Chinese and Japanese are anything to go by - Very Expensive... The Japanese have been touting Tokyo to Osaka (IIRC) Maglev for a while but cost is proving prohibitive (£60bn+). The Chinese have also put the brakes on their system preferring standard LGVs for cost reasons.
The Transrapid Test Track in Germany is being dismantled next year
The construction on the Chūō Shinkansen has been commited to the general plan with all neccesary approvals granted, construction should be starting in 2014.
It happens to reuse the length of the test track which is very smart in my opinion (would we have that sort of forward planning on test track construction here I wonder?).
Part of the reason for the enormous cost of the route is the fact that 60% of it will be in deep tunnels sized for 500kph running (including apparently atleast one underground station), which as you can imagine are enormous.
I haven't heard anything about the Elmsland test track being decommisioned, they are still testing new iterations of design vehicles so I don't know about that....
Frankly we should probably build a Transrapid type maglev route on one of our self contained ~100 mile long intercity corridors (London-Norwich comes to mind) so we can actually gather real world data about the system and how it behaves and on how much it actually costs to build.
But we don't get that kind of spending on infrastructure to justify it as an experiment.