I am building a dedicated H/T Room 12" Feet Wide 16" feet Long and 8" feet high ceiling all will be done in Quiet rock sound prooofing drywall and two by six construction.Currently Have a Samsung 50" HD Plasma. I was considering going with somthing larger 60 70 in the Rear Projection format which one out of the Three about to be released : 65" Brillian 1080 LCOS , JVC-Dila 1080 or Samsung 60"---70" with there XHD3 Chip
I'd think about getting a front projector and a quality screen. IMO rear projectors peak in picture quality around 50", over that you start making trade-offs. Not to say there aren't some excellent products in that size, just that you will get more from your money buying a quality 1080p LCOS/DLP front projector.