Better than a plasma - I've just switched
I bought the 46" version of this TV 2 weeks ago, sold my crappy 50" Plasma that had image retention problems from day 1, was less than a year old, and let me tell you, LED LCD beats it hand down!
Everybody who's been round my house since I got the TV remarks on how much better the picture is, and that's just standard upscalled cable on Virgin V+ box. Even my wifes friends who know pretty much nothing about technology are amazed at the picture.
The blacks are so much better, it uses less power, pumps out less heat, and oh, I can leave this with a static image on screen or play a game for hours on end and it won't burn in. Plasma's are more trouble than they're worth - will never buy one again after viewing this set.
Set it to SmartLED mode and 100Hz mode to low and sport becomes very watchable, then turn 100Hz off for 1080p/24hz movies then it trounces any Plasma I've watched for black levels and image detail (if you take the time to calibrate - AVForums has some great guides on this).
If you can, sell you're Fred Flintstone Plasma and get one of these: no screen retention, plasma beating blacks (0 cmd blacks - what Plasma can get near?), no Plain-bow effect. Its win-win-win!