I don't know much about HDTV's but after doing a bit of research I found a few articles that had helpful info:

http://tech.yahoo.com/blogs/null/29221
http://tech.yahoo.com/blog/null/8807

These two articles talk about the size of the TV, 720p vs. 1080p, and if the 1080p upgrade is really worth it.

Claims that very few consumers can actually tell the difference between 720p and 1080p. Also that upgrading from a 720p model to a similar 1080p model could add another 50% to the price, for the limited benefits it gives. One more thing I found interesting was this:

"You might be surprised: If you sit a normal distance from your TV, (say, 10 to 15 feet) you'll need a fairly large set before even basic HDTV quality starts to become noticeable. At 15 feet away, you need a 45-inch set to see any of the benefit of 720p and nearly an 80-inch set for 1080p to make a difference. I don't know about you, but an 80-inch plasma isn't currently in my budget."

It's only one source, so take it for what it's worth, but it seems many people are buying the latest and greatest without actually understanding the benefits, if any, from a 1080p set.