Game lag is apparently an issue, but the picture on that Samsung DLP is *outstanding*.
One other issue with DLPs is limited vertical viewing angle. They are also of course not as flat as plasma TV's, at about 12" thick.. and you'll need to replace the bulb every 18 months or so at about $175 a pop. But the picture on that TV is better than anything else in the price range, and better than even the best plasmas.