Mr. Johnston, you may want to check out this forum: avsforum.com. There are chat rooms for both Plasma, DLP, and LCD/rpt displays. Be sure to read the FAQ sections in each room. They are very helpful, and will answer a lot of questions that you may have. I am looking at 42/43" plasmas and the Sony GW XBR LCD/RPT 50" that is to be released this Ocotber. Onecall.com has the specs on the sony.
I have looked first hand at these displays and have to say that the Plasma's get the nod in picture quality over DLP and LCD/RPT sets, which are both nice. The plsama's when fed a quality progressive scan or HD sat image are breathtaking.
Hackmaster pointed out that one of the flaws with plasma is poor black levels. The older generation sets indeed suffered this. However the current genreation sets have outstanding blacklevels. The knock I have with LCD/RPT's is that the black level's are a real weakness. Currently Panasonic has a 40" and 45" LCD/RPT that suffers from weak black levels. The new Sony XBR's are said to have improved blacks due to inovative circuit designs. Only time will tell.
Pixelation in plasmas has been greatly reduce and in most of the sets from NEC, Pioneer, Panasonic, and Fujitsu, the onboard scalers do excellent jobs at presenting smooth images without image fragmentation.
Signal source is a key to good viewing on plasma's, as they really show the flaws inherent in poor signal quality provided by most cable companies. Beware the digital cable tag, as the signal is not a true digital feed comnpared to that of Direct TV, Dishnetowrk, or your local over the ari broadcasts (where available). This holds true for both LCD and DLP displays as well.
The consensus at the avsforum.com site is that the Panasonic's are the sets to beat, followed closely by the NEC's, Pioneer, Fujitsu, in no particular order. I am a couple of months out from pulling the triger on a plasma, and the time I have spent on avsforum.com has been invaluable consdiereing the capital investment.
Lastly, prices have fallen dramatically in the last 4-6 weeks on 42" plasma displays. The Pioneer 433CMX can be had for around $4,000 shipped from a number of very reputable on line retailers. I'll send you some links that you may find helpful.
Best of luck,
Rodney