1080i is good for things where there isnt a lot of fast movement (ie Dr. Phil) because the frames are interlaced and fast movement can make it a bit blurry. 720p isn't quite as crisp a picture as 1080i, but the frames aren't interlaced so it will not be blurry no matter what speed the objects are moving on screen (good for sports channels and video games). 1080p combines the the sharper picture of 1080i and the non-interlaced frames of 720p, and is therefore the best. there are no television networks that currently can handle 1080p, but they will come with time. blu-ray movies usually are in 1080p.