I went with the the Pioneer 4350, w/the table top swivel stand from TV Authority. I really liked Monitor Outlet.com but the no risk 30 day return feature from TV Authority was my safety net in case something went wrong and I didn't like the TV. Just ship it back with no restocking fees etc. I set it up in my bedroom and it looks awesome. I'm waiting for the new Dish 942 HD receiver to come out, (which BTW is listed on their web site now. Their customer service reps told me yesterday that it will be officially introduced next week) and this thing will really rock the room. I preferred the Pioneer over the Panasonic due to a few reasons:
1.) the 4350 has many new features previously only available with the Elite series like a new color filter which claims to enhance the contrast ratio and color brightness; cable card slot, dual tuners, HDMI etc
2.) it is the latest offering (3rd generation I think) from Pioneer
3.) many of the high end A/V stores all say terrific things about Pioneer plasma's (including CNET)in terms of durability and performance
4.) looks are stunning and very high tech even when turned off
5.) the TH-42PX25 is an "older" model meaning they are about to release the next version any day (TH-42PX50U/P)
6.) Liked the idea of the separate media box (even though it does have a faint "buzz" to it) in case something went wrong with the TV.....might not have to ship the entrire unit back, just the box
7.) Every one claims the "black levels" with the Panasonic can not be beat, but to my eye, Pioneer looks just as good and the difference is not noticeable.
Good luck with what ever your choose, but no buyers remorse here so far!