Loudthinking points out a possible problem for MS - Longhorn is looking like more of a problem than a solution to some people. The early adopters are already moving - for all the noise about tablets, take a look around at the next trade show you attend - it's likely that you'll see more mac notebooks than you might expect. I've said before that the issue Longhorn will face is not the actual cost of migration - it's the perceived cost of migration. if the meme gets around that "it's not worth the trouble", then MS is going to have a problem on its hands.