The difference in HD of 720 and 1080p is very minor.
This. The game is going to look fantastic on either system. It will just look better on a PC that can handle 1080p and has a monitor/TV that can handle it and is big enough to even notice the difference. If you are gonna play it on 20" monitor, I doubt it would be much of a noticeable difference. Now if you are hooking your PC up to a 36"+ LCD/Plasma TV, then yeah you'll see the improvement. I bet that a majority of PC players will be playing at 720p on release, because unless you got a super rig there will be a sizable performance hit on the game, and having the game run smoothly is more important than a better resolution IMO.
Don't forget about viewing distance. People tend to sit within a few feet of their computer monitors, while for TVs sitting 6, 8, 10+ feet away isn't uncommon. For this reason, resolution will matter even less on a TV than it does on a monitor for many people.
There's charts and guides all over the place online, but here's one I found on Google just now to show proper viewing distance depending on your resolution and screen size, which seems accurate at a glance. http://s3.carltonbale.com/resolution_chart.html
I think it's worth looking at for people concerned about the difference between 720p and 1080p on their TV. If you're like me, you may find that you already sit far enough away that there's really no noticeable difference between the two. And for those who do sit close enough that they might notice a difference, it's still worth noting that it's not a very large difference. If you're a videophile who optimizes screen size and viewing distance so that you can sit close to the screen (closer than, say, the average person who has a moderately sized TV and sits back on the couch) and still get the absolute best
possible picture, it might be something to think about. Others shouldn't really be too concerned about it IMO. Edited, Jun 27th 2010 2:17pm by Susanoh