Robert - Excellent points.
AK - I've seen as low as 51k on Ebay:
eBay Motors: BMW : M3 (item 320336508613 end time Feb-08-09 16:49:07 PST)
It wasn't uncommon to have sold left over M3 coupes at high 50s so I can certainly see high 40's soon.
ps I would seriously buy that one you have linked if it was Silverstone or White.