It would seem anything is possible in F1. Magny-Cours might even remain on the calendar next year as was commented by Keith on F1Fanatic. The US GP might even make a comeback too. Actually that would be good, it would be nice to have different tracks.
The really interesting track would be Abu Dhabi. But looking at the calendar presented by Keith, it seems odd that the F1 circus should travel from Europe to Singapore then back to the Middle East at Abu Dhabi. They should go from Europe to Abu Dhabi first then travel to the east to Singapore, Japan and China before finishing in Brazil. That would help the logistics and jetlag.