G11, all the way!
Much better camera than the 650IS, it retains the articulate screen, and it's got much better ISO response. It's also roughly the same size as the lost camera, and you're only take a small hit in zoom capability (5x vs the 6x on the 650IS).
The s90 is a fantastic camera, but it would seem like a downgrade. And you don't get much zoom, either (3.5x).