Receiver Choice
I would definately go with Pwr choice for 7 speakers. Although, the HDMI choice is right up there. I would be looking for a combination of the two. I would want to hook up my Laser Disc, DVD, Xbox, Satellite, DVD Recorder, Vhs, ect... all up to the Receiver with only One HDMI hookup to the Projector. Then I would use the Receiver as Pre-Amp and use the line outputs to a dedicated Amp like the one I heard Axiom was currently working on.
However, If I decided to use the Internal Amp on the Receiver, The more Power the Better. I like to have a lot of head room w/ power in reserve.