koko37 - the window for holding the Summer Olympics, as set by the IOC, is 15 July to 31 August, so I think a December Olympics is out of the question.

Qatar requested to hold them October due to the hot weather, as they are allowed to do according to the IOC conditions, but the IOC decided that it was unacceptable to hold them in October in this case (or they at least used this as the excuse for rejecting Qatar's bid - since they've previous Olympics have been held in October).