ED plasmas with upscaling DVD players

So I'm ready to upgrade both my TV and my DVD player.


I'm leaning toward getting a 42" ED plasma (probably Panny), which I would pair with one of the new upscaling universal players like the Pioneer DV-59 or the Denon DVD-5900. (I also have a SA 3100HD cable box with about eight HD channels through Time Warner.)


So here's my question: is there any advantage to upscaling the DVD signal to, say, 720p if you are using an ED display? On paper this wouldn't seem to make sense, since ideally you would map the 480p DVD signal to the 480p display. But we all know how amazing HD signals look on ED displays (and Fox, at 480p, looks like crap next to true HD signals, as we'll see today during the NFL playoff games).


I'm aware that upscaling the DVD signal doesn't actually add resolution, but people who own the upscaling players claim to be amazed by the results.


The upscaling players I'm considering are fairly expensive, so if upscaling won't do me any good, I'll probably go with a cheaper player.


That said, another question is how a 720p upscaled DVD signal would look on an HD plasma. Would the increase in PQ be worth the extra cost?