This new refresh of the windows mobile line is a very bold move by Microsoft. I'm really surprised they threw out all the existing winmo architecture and started fresh. The carrier network that supports WM7 will mean lots of choices for consumers as well. Not only that, they seem to really be emphasizing consistency across devices with the three buttons (start, search, back). This is undoubtedly uncharacteristic of how the winmo division has previously operated.
Most of all, todays announcement shows me they get it. I had always written off windows mobile as an OS, and after looking at things a bit, I'm considering WM7 for my next phone OS.