^^^Indeed!
At 11 feet, I would certainly recommend a larger screen size than 50".
SMPTE would recommend a 81" screen size for that distance. Obviously, outside of a front projection system, that isn't really an option
If you can really block out the light from that window and make the room dim (or, ideally, totally pitch black), you could go with a front projection system though. If you're interested in that approach, we can certainly offer some projector and screen recommendations
If you want to stick with a flat panel though, there are a few options. A 65" screen size would actually be at the "small" end of the recommended screen size scale for an 11 foot viewing distance. You'd have just a little over a 24 degree field of view with a 65" screen from 11 feet away.
The other option is to just move the display closer! If you put the display on a TV stand, you can easily bring the screen 2, or maybe 3 feet closer to your eyes. For example, if the display is 9 feet from your eyes instead of 11 feet, a 52" screen size would give you the same 24 degree field of view as the 65" size from 11 feet.
In any case, once you go above the 50-55" screen size range, LCDs get really expensive. If you're sticking with the 11 foot viewing distance, a 60-65" plasma is the only way to go, IMO. The Panasonic TC-P65V10 would be an excellent choice in that situation.
If you can move the screen a little bit closer, or you are simply satisfied with a smaller field of view and screen size, then the Pioneer KRP-600M 60" Monitor comes into play. The 50" KRP-500M might also be ok if you can shorten the viewing distance.
The KRP plasmas are basically identical to the Signature Elite Kuro Monitors. They are unmatched in picture quality - whether the room is dim or bright. Note though that the KRP models are monitors only - they do not come with speakers, they do not come with a stand, and they do not have internal ATSC/NTSC tuners. So if you buy a KRP, you will need separate speakers, you'll need to buy a stand or a wall-mount separately and you will need an outboard cable/satellite box or a digitial tuner box if you want to watch TV.
I'd stay away from Samsung's LCDs, simply because they all use a super glossy screen surface (which is such a shame

) ANY light is strongly reflected from Samsung's screens these days. I really hope they change that design because in every other way, they are great TVs! But that super glossy screen is just a deal breaker in anything other than a totally dark room - in which case, a Panasonic plasma is even better!
If the room is going to be bright and the Pioneer KRP models don't cut it for you price wise or size wise, then a Sony W5100 LCD would be a pretty good choice IMO.
So, bottom line:
- get a bigger screen size if you're keeping the 11 foot viewing distance
- consider moving the display closer if you want to keep the screen size (and cost) down.
- The Pioneer KRP plasma Monitors are the best price for the best performance out there.
- The Panasonic V10 and G10 plasmas are a great second choice if you can put some drapes over the windows and keep the room on the dimmer side
- If the room is going to be bright and the KRP Monitors are too expensive, the Sony W5100 LCDs are a pretty good option.
Best of luck!