I am in no way an expert, but from what I have read Dolby Pro Logic IIx will take any 5.1 source and turn it into 7.1. If you want to run a 7.1 setup and are looking to buy a receiver I would make sure it has Dolby IIx. I beleive it will even make 2 channel sources utilize the 7.1 setup also although it probably would not sound that great (for movies anyway)

Pioneer VSX94TXH, M22ti fronts, VP150ti, QS8ti side + rear, SVS PB13 Ultra, Oppo BDP93