Wow, I'm really surprised that this is turning out to be an ongoing issue with newer Panny plasmas. Originally, it was supposed to be isolated to the 6/60/600 series. I had my 600u replaced under warranty almost 2 years ago now with a 42pz700. I can honestly say, I still have not seen any signs of the 'snakes' or 'ants' like I had with my original TV. It still looks great. I think the problem is much more isolated now, otherwise, we'd be seeing a lot more complaints about this issue. With the 6xx series, it was almost guaranteed that you'd see the problem.
If it ain't in HD, it ain't worth watching!