Some of you seem to have some misconceptions in regard to how size is properly measured on a display device. It isn't measured in inches but in field of view from your viewing distance. You can figure this out with the Pythagorean Theorem and some trigonometry.
A 30" monitor viewed from 2 feet is the exact same size as a 50" TV viewed from 3.5 feet. Both cases give about a 55° FOV. If you sit farther than 3.5 feet from that 50" TV (and just about everyone does), it is SMALLER than the 30" monitor at 2 feet and will give a less immersive presentation.
THX actually recommends a 40° FOV for viewing, so a 30" monitor at a two foot viewing distance is actually way too big according to them. You would have to sit about 3 feet from a 30" monitor to get a 40° FOV and about 5 feet from a 50" TV to get the same; and to reiterate, if you sit farther than 5 feet from that TV it is SMALLER than the 30" monitor at 3 feet.
So anyone saying a display device is too small without specifying viewing distance has a rather fundamental misunderstanding of the issue.
All true, but your missed something. You are assuming that all display devices have the same characteristics and they do not. The differences between a good Plasma TV and 30 IPS panel are very noticable. A larger screen is more immersive. It has the psycholoical effect of pulling you into the scene that the director created and this cannot be described with trig.