Distance/Screen SIze Formula?


My husband and I are debating between a 50" and a 60" flat panel television for our living room. Although the room is very long , it is not very wide and we would be veiwing the televsion from aprox.12 feet from the screen. Does 60" seem like too large a screen for that distance or can we go for it?We hate the feeling of sitting in the first few rows of a movie theatre.........hence our concern. Can anyone help?
lel
I know there is a formula for this, which I disregard. I sit about 12 ft. from my 65 incher. I also have a projector . The screen comes down in front of this tv. This screen is a 92 diag.---After watching HD_DVDs or a great football game in HD---going back to my 65set----IT seems small. Hey, we're all different. Step off the distance at home--then step it off at the tv showroom---using different sizes of displays and see what is to-close---for you---not somebody's opinion.
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I sit about 10' from my 61" plasma. Works for me, doesn't seem too large, and I'm not one of those types that sits in the front row of movie theatres either...

TVs typically don't come close to the field of view that you get in a movie theatre, which can be like 30-45 degrees or so. My 61" plasma has a viewing angle of about 25 degrees at 10 feet, if I do my math right...