Well, no they didn’t.
However while playing with the Developer Preview on my BUILD tablet it struck me as odd that a snapped app takes a very narrow view rather than a 50/50 split.
The app is notified when the mode is changed so it can switch its appearance to a different XAML (or HTML) view, optimized for the smaller space.
That’s a lot of effort just to get two apps side-by-side…
Think about it!
The snapped UI is a phone UI!
I’m sure they’d have loved to announced Windows Phone 8 and show how you can elegantly run phone and tablet apps on the same device (from the same binary in fact) – significantly better than the 2x mode on the iPad.
Unfortunately doing so would have reduced Windows Phone 7′s traction to zero so they just called it “Metro Snap” and everybody nodded and clapped anyway!
I’m betting sometime next year they’ll announce that Windows Phone 8 is basically Windows 8 (ARM) with some customizations.
Developers won’t need to do anything to make their Win8 apps run on the phone as they’ll already have done the work without even knowing!