The screen pixel resolution (720 vs 1080) and whether the screen does progressive scan (i vs p). With 1080, you'll have a 1920x1080 resolution, while you'll have a 1280x720 resolution for 720. The "i" stands for interlaced and the "p" stands for progressive-scan. Ideally, you'd want a high screen pixel resolution and progressive scan, so a 1080p screen is the best (although outside of Blu-Ray and HD-DVD, you may not achieve 1080p). If you have to sacrifice one for the other, you have to determine what type of things you watch on your TV and the size of the screen. If you watch action movies or sports a lot and you're thinking about getting a smaller screen, I would recommend going with the progressive scan (720p) over the resolution (1080i). The reason for this is because progressive scan handles fast-moving images a lot better than non-progressive scan TVs. But another factor that you should consider is the refresh speed (the smaller the better). For larger screens, I believe the 1080i will be better. Here are a couple of links that will explain this better. http://reviews.cnet.com/4520-7608_7-1016109-3.html?tag=tnav http://www.cnet.com/4520-7874_1-5137915-1.html

go wit the 1080 pixels