Forget about smooth UI. Smartphones will have quadcores and >1GHz next year when first Nokia WP7 might arrive if not delayed. What will be next features after big screens, fotos, games? Maybe totally networking with all kinde of devices and multiple standards? Maemo had all Linux communication stacks onboards, will full blown desktop linux behind it. Hard to imaging WP7 can compete.

=> Nokia now has
1) "Ecosystem" with marginable market share (not even 3rd ...)
2) Less advanced platform that has been abondaned by others already (Samsung, Motorola)
3) Lost control of both ecosystem and platform
4) Ruined reputation of its own ecosystem and platform and its own reputation for developers also - would you invest in Nokia WP7 now after having invested in QT/Symbian? Or go to Android ...

The winner of the deal seems to be MS. But by the delay of 1 yr. until delivery of Nokia WP7 phones is too long - in this time Symbian will eventually die (at least converning market share and OVI) because everybody knows its an abandoned platform.