Go look at them in person. I can tell you from my experience as a casual viewer (don't own one myself) that I don't like DLP rear or front projection because of color separation. If you talk, chew, move your head or eyes while watching, you will see red, green and blue shifts all over the image. I saw a few sets that got around this at CES, but they were few and far between.

3LCD rear projection provided by far the best images I have ever seen on any display. Not as widely adopted as DLP, it's becoming more common from a number of manufacturers nonetheless. Sony and others at various price points. It's an Epson technology (DLP is Texas Instruments) and was heavily promoted at CES earlier this month. Simply stunning displays at Epson's own booth and their (and partners) 3LCD technology showcase booth. http://www.3lcd.com Worth looking into.

Also worth looking into is a good scaler if the one built into the set isn't the greatest. Affordable and versatile: http://www.dvdo.com. It also handles video switching and can go from one input topology to a different output. I've been recommending it as an expensive (possible) way to connect a Mac Mini to an HD set that lacks DVI (though I'd love someone to confirm it works )

Bruno