A feeling that I'm not buying the same OS each year.
Personally, I think Microsoft's strategy of bringing back the hybrid desktop/tablet, where you can do tablet-type things on the road/in bed, then drop it into a dock and go back to mouse and keyboard for work, is pretty sound now. I like what they've done with Windows 8. I like that they're trying.
What do I want from Apple? Probably something I don't know I want. I want to be able to drop an iPad into an iMac enclosure and have a hybrid work area. I want iCloud to be more than some weird, feature-free Dropbox (the new organization structure sounds like a misery for anyone with more than a handful of files). I want them to fix Finder and rethink the Dock.
But this is like asking what I want from an iPhone before I ever saw one, and I think most people's ideas of what they wanted were so wildly off, and then Steve comes out and says "You want this" and he's right. That's what I want from them, to know me better than myself.