It all comes down to what you want. The best way to make a decision is to actually go to a store and look at the sets. If you're serious about buying, they shouldn't have a problem hooking up both sets to a blue ray or HD-DVD player for you. Many stores will happily let you bring in a PS3/360 to hook up and test out. That being said, I personally own a 4065F and it's a beautiful TV. I went with the LCD for 3 main reasons: 1) I got a good deal on it and money was tight. I couldn't afford something bigger than about 42 while getting a quality set. This did limit my options as far as the amount of Plasmas I could consider. Still, I actually almost bought a panasonic pz77u at sears (but couldn't find my damn card). 2) I wanted to use it for a computer monitor quite heavily. I mainly use it for my computer and 360 gaming. I do watch HD-DVDs on it from time to time, and I do watch things like football and such on it (other than that I don't watch much actual TV). 3) IR bothers me.
Now, I'm not talking about permanent damage, which I'm not worried about. Plasma technology has evolved such that permanent damage is really a thing of the past if you take care of your set. For the first 100 hours or so you should be more careful. Most people recomend about a 100 hour break in period where you don't allow any static images to remain on the screen. People say that running the xbox 360 music visualization full screen is great for this... though you could play a bunch of movies or do whatever. After that period you are pretty safe. Any IR should be fixable by running something like the visualization thinger for a while... or using the TVs utility. I personally didn't opt to do this, because I would have static images on a lot, and though the break in period wasn't a problem, I didn't want to have to deal with further conditioning after PC or xbox use.
Now, that being said, as a 65F series owner, I would say that you should definitely at least consider some of the plasma TVs on the market in your price range. While the pioneer sets may be a bit more than you want to spend, there are good offerings from Samsung (like the 5084) and Panasonic (50pz700U or 750U) that I bet you would love. If you are going to be using this for a theater TV mainly, Plasmas are going to be VERY strong contenders... If I was going bigger than 40... and watching mostly movies... I would probably have opted for a nice plasma without question (gaming on plasmas is also amazing for what it's worth). Don't get me wrong, I absolutely love my 4065F, and I'll have it for quite some time after I graduate, but I definitely could get by using my 24" LCD for a computer monitor if someone wants to donate me a kuro
Also FWIW, statistically plasmas do have a higher failure rate and do have a slightly higher cost per repair than LCDs. However, realize that the failure rate with both technologies is pretty low. If you are really worried about failure, get a warranty from Mack (
www.mackcam.com). Obviously, warranty plans are designed to make the company supplying them money, but Mack plans tend to be a good deal cheaper than what you would get at BB or CC. The best way to get piece of mind IMHO... if you think you need that piece of mind anyway....