Well, I pulled the trigger and bought the 51" Hitachi f59 today from Sears.
$949 for the TV
$489 for the 5 year warranty
I was going to get the 57", but it was HUGE and thought it was too big for my room - I am only 8 feet away from the TV, so I think it would just overwhelm the wife and I, especially going from a 32" TV.
Don't get me wrong - I was BLOWN AWAY by the SONY SXRD at Circuit City with the Hawaii feed, but not $3000+ more blown away.
Reason I went with the more expensive Sears warranty is that it is a much better warranty than CC or Best Buy or any of the 3rd party ones. The kicker was the once a year PM I get, where they clean out, adjust, tune up, etc. the TV - I am thinking that will perhaps extend the life of the TV quite a bit vs. no PM service once a year.
I was pretty impressed with the untweaked picture of the Hitachi in the store, though at Circuit City they had a bad feed on all of the RP TVs (except the Sonys).
CC was about $300+ higher, warranty wasn't as good or as long, and the 5 TV salespeople there ignored me to watch the soccer game on TV even though I told one of them I was there to buy today. Idiots.