It seems they don't work well, don't have enough apps, and aren't designed sensibly. Microsoft has failed again, which doesn't surprise me at all.
PC's are dead, and that's a fact. It will take a while before Microsoft realizes it's become a zombie, but that day will come. But what surprises me is that no one ever talks about the elephant in the room: how the interface looks.
I mean, take a gander at that image up there. It's the ugliest imaginable interface. But this is nothing new for Microsoft. They've always had unattractive GUI's. They can't design the look of anything. It's like they farmed out the "looks" job to a group of cavemen. And straight cavemen, at that.
And that's the heart of the matter. Microsoft has never consulted with a gay male designer. I'm quite sure of this. If they had, the interface wouldn't look like a piece of garbage.
If I have to work at my computer all day, I do not want to look at that. Macs not only work perfectly (and don't have viruses); they also look gorgeous. Not to mention the fact that they're virtually silent, as opposed to the portentous noises one hears whenever one does something on a PC. It reacts like an old man, who has to wheeze and get up when you ask for something. Tired.
Go buy a Mac today. You'll be happy you did.