I know some guys have larger, but I have a 30" dell and I couldn't really imagine having a larger monitor than that. it seems to be a perfect size, everything is proportional and within easy site, but I'd think you'd have to be looking all over the place and moving your head around on anything larger.
Also, correct me if I'm wrong, but don't even 1080p monitors have a fairly low resolution compared to larger computer monitors? My 30" resolution is 1600x2860, the resolution of 1080p is 1920x1080, almost 50% fewer pixels. So wouldn't that mean that while the screen is substantially larger, there will either be lost detail or clarity or what is actually displayed will just be magnified (a 1" tall icon on my screen would be 2" tall but lower quality on a HDTV screen)?