The burn in will still be present, and with a game like WoW, it will be bad.

I know because I have a Sieres 7 Samsung and tried it myself to prove it to a friend.

However, the price and colour/brightness makes it a tough decision....

I'd still go with an LCD or LED if you can afford it.

As for the space issue, well..... if thats a concern, maybe you should spend the money on a 30" LCD monitor? (the Dell 30" screens are amazing, I have 3 and wouldn't change them for the world! )