I was sitting in the auction room until the "R"s (there's only so long you can sit there, and it was a very long process) and it was interesting to watch the .cm names in particular sell.
I get the impression that the first couple broke the ice, and after that there was something of a "well if others have tested the water, it must be ok" - and that's why stuff like Vegas.cm went so high. I suppose if you're a "large" domainer it's no hassle at all to take a gamble on ONE really great name on an extension which may/may not catch on - if it does catch on you'll do well with that name, and if it doesn't no big deal. I was bidding on golf.cm (and bowlingballs.co.uk for a while) for exactly the same reason, but at some point it no longer makes sense even as a high risk/high return play.
Some of the 3-word .de domains like the "free credit report" one apparently mystified the German speakers that I talked to afterwards, because they were more like a dictionary word-by-word translation rather than the "correct" German word, and would never get used in practice in Germany. If that's the case, it's no wonder none of them got higher than the reserve.