Here's a pic of our Family Room. The room is 15 x 18 so a 7.1 system would have been overkill - overall, our 5.0 (or 5.5 if you want to get specific) is more than adequate for the room and the two of us.

Current equipment includes:

Onkyo TX-SR701
Oppo OPDV971H
Pioneer PDP-4312

Speakers:

Def Tech BP 2006TL (Front Left & Right)
Def Tech C/L/R/ 2300 (Center)
Def Tech BPVX/P (Rear Surrounds)

Misc Items:

Modded X-Box running Avalaunch and XBMC
Nintendo Game Cube
Onkyo DS-A2 for iPod integration
Belkin PureAV PF60

PS The weird lines on the plasma were due to sun shining through window shutters on the rear wall. The Pioneer definitely has a better picture than what you see in the pic. ;)

http://www.suclla.com/images/hometheater.jpg

I'm going to mount my TV above the fireplace as well.
Do you find that you get neck strain after long movie sessions?
Btw: I like the component shelf to the right. Was that there initially?

Initially, you would think that neck strain would be a problem, but in reality its not elevated enough for that. Even when we have friends over doing the bean bag thing on the floor its still not an issue. The only problem we thought we might encounter was heat dissipation from the fireplace but even that hasn't become an issue for the screen or the center channel.

The component shelf was already there, though its intended use is for a 36" Television - obviously its a throwback to time before home theater... The next step for me is to install some shelves and lighting in there so I can separate some of the components and lessen the heat they create for the other units and have some light for troubleshooting cable connections.

A quick note: the shelf also works nicely to route cables behind the wall from the tv to the components.

in reality, it's not elevated enough for that

That's great to hear! I'll be in the same situation soon.
I like your floor, too. I'm a light-wood kind of person :-)
What is the opening behind the rear front speaker?

That seems to be another opening that was created for storage. I'm in the process of figuring out some kind of doors or cover for that area. Basically, that's where we store extra remotes and games/game console accessories, etc. Its somewhat convenient but an eyesore for sure.

The wood is a manufactured maple floor. It is gorgeous up close with a lot of character but if you have pets or are klutzy I would recommend something a bit harder (bamboo perhaps...). Our pug has given the floor a good beating and we've nicked it in a couple of places as well. Someday in the near future we'll refinish it with what they call a "diamond finish" and hopefully that'll help...