I have a 19" Samsung 957DF CRT which has a Dynaflat, which is a shadow mask flat tube, really quite nice for the money, £250 when I bought it new... now you can get it for about £220. I recently purchased a 17" samsung 172T TFT screen... it has the same viewable area as the 19" CRT... via DVI its really sharp and the colours are amazing, but with a response time of <24ms you still get what is called ghosting... this is where you can just see the place where the image was previously.
I play Counterstrike a lot on a laptop with a 15" screen and whilst its not anywhere as nice as the CRT your eyes get used to it and you don't notice the ghosting much. AOC are making some very low response time screens which might be less ghosty for gaming, but after spending ~£400 on the tft I'd have to say that the CRT is still king for gaming... but I think I'll try and adapt to the TFT as it is wall mountable and with my PC being a HTPC with cordless mouse and keyboard it would be great to have a monitor for gaming in my living room but the PC linked to widescreen tv also. I've played a fair bit of BF1942 on it and its not too bad, but the best screens for gaming I have read about with 14ms response time have been made by AOC.