Some interesting stuff being mentioned here. One thing in particular caught my attention:
"Desktop apps will also use colorful tiles by default, and developers will have the option to create richer versions."
That sounds like desktop apps will be able to have live tiles. If that's right, then I vehemently hope we'll get an update for Outlook 2013 that takes advantage of that.
The option to show the desktop behind the live tiles also sounds interesting (though I'll have to see if that's not too visually noisy). It does seem like MS is trying to improve the integration between the two worlds, which is a good thing imo.
New shortcut key for search, WinKey + S, which is also used by the Send to OneNote tool. I don't use that tool, but I'm sure that's going to piss off someone.