I think some people are putting way too much into this. Nokia cannot abandon Symbian and MeeGo just like that. They cannot make a WP7 phone overnight.

Nokia most certainly have a dual core A9 ready, but at the moment the only OS ready for shipping on it is WP7 (in addition to Android, maybe). Symbian needs some work on that device and MeeGo needs lots of work. Question is - what is MS willing to pay and do for Nokia to sell it with WP7.