Getting a Plasma TV for Xbox 360 - Is 1080P worth the extra $$$?

[LocustHorde]

I'm going to be buying a plasma TV in a few days and would like to know if TV with 1080P technology is significantly better than a 720P TV. I'll be using it to play lots of xbox 360, so I would like to have a really nice viewing experience when playing. Price is really not an issue(I'm looking in the 50-58" range), but I would not want to waste the extra money if it's only marginally better than a 720P set.

So basically, I could get a bigger set(58") w/ 720P or I could go a notch lower and get a 50" w/ 1080P.