I'd like to maintain the quality of the colors/performance and the readability of texts are astonishing on both of my TVs. Maybe something is wrong with my eyes, and yes they do have bigger pixels than a classical PC monitor, but I'm 1.20m away from my primary 37" TV, and 2m away from the 50" one, and I can't even distinguish them. Actually, I feel quite more comfortable than with my former 24" SAMSUNG Monitor, even for computing, I don't even remember how I got rid of it. I would never step back for a screen under 30". BF3 in 3D with a huge field of view is amazing.
Obviously, a decent TV IS way more expensive than a PC Monitor -- I got the 37" during a bargain offer for 899$, and the 3D-Ready 50" for 2249$, the price of 5+ nice PC gaming monitors or a gaming computer, but much less than what it used to cost a couple of years ago -- and obviously if you want to play from your couch, you may need to lower the resolution to be able to read texts, especially for MMOs in which there's a lot to read. In games like AC or GTA, it is none of a problem at all for me. But assuming you can invest the price, I do claim TVs definitely are "a excellent horse to bet on".
(Sorry if my English sometimes is quite of a clumsy one, I don't master all of the typically English expressions...)