The latest generation of LCD are very good for gaming. There are a few words of caution to observe before buying ANY LCD. You can get a good 17" LCD for $200 on sale, and remember thats as big as an 18" CRT would be. 19" LCD can be had for $300-$350 for a nice one....now thats cheap! Word on the street is 19" prices wil plunge by the end of the year.
#1) Specs from manufacturers are NOT standardized. One companies 400:1 contrast ratio looks better than another companies 500:1 Same with Brightness and ESPECIALLY response time. A LCD rated by the manufacturer at 12ms panel may AVERAGE 25 ms in most situations, while another rates at 16ms may average only 20ms. You cannot trust just reading the numbers, several good review sites have excellent ratings for many common pannels giving true preformance comparisons. IN ANY CASE its always best to look at the panel yourself IN PERSON before making the purchase.
#2) If you do any high end graphics work, be sure you panel is not a 6bit panel...these often have insanly nice response times, but do not display true 24bit color 8-8-8 (they only do 6-6-6). Its not a big deal for gamers, but its a little bit of an issue for high end graphics editing. Finding out if a panel is 6 or 8 bit color can be difficult (its almost never on the box)...when in doubt, ask the manufacturer.
#3) Unless your savings insane amounts of $$$ and are willing to role the dice, its not a good idea to but an LCD online. DEAD PIXELS isnt a huge issue, but it can crop up on even the best manufacturers panels. Many online retailers will not accept returns/refunds for panels unless there are MANY MANY bad pixels. Buying at a local store gives you the ability to bring it right back or better yet, check it out in the store. (all white/all black/red/Green/blue screens and look for problems).
#4) An LCD pretty much locks you into a resolution. 99% are 1280x1024, a few large panels are 1600x1200. Either way, lowering the resolution will make tings look pretty bad as pixels are interpolated. unlike a CRT the LCD only looks good at one resolution. If you cant play a game smoothly at your LCSs native resolution, you may not be able to effectivly lower the resolution without making things look like crap.
Ahh well...aint life fun!
BTW I love my LCD, Ive got an overpriced 19" sony that I found with a huge discount.