For the TV in thinking 42'' or 46'' LCD.
Room layout would be TV on the 9ft wall with seating being approx. 10ft back. I might also want to run a 7.1 arrangement. Small towers up front along with center. In wall surround left and right and ceiling surround back.
Are you
against the idea of a projector? I played with my PJ's pic at the wall for a
whole week and decided on 42 degrees. This equates to 106" from 10'. Now, I'm not saying that everyone would like this, but just wanted to put 42" in perspective. THX
recommends 90" from that distance (equivalent to the middle of a theater). FWIW.
To add to highfigh's thoughts, bass trapping becomes more important the smaller the room becomes. While you might not have the money (nor permission) to put up treatments, DIY can be very affordable especially if you use mineral wool instead of fiberglass, and less that, strategically placed curtains, etc will help too. You can search the acoustics forum here for stealth or artsy type treatments as well.