Rear Projection
Don't necessarily agree with the comments regarding rear projection TVs. The viewing area is limited on certain models, many newer models provide very sharp and bright off-axis viewing, which was typically the case on older RP models.
Size is a factor with RPTVs, however this has been offset as of late with quality of picture and price difference as opposed to some of the plasma, DLP and projector offerings. Plasmas have incredible color saturation, but fall short when it comes to blacker than black recreation. DLPs are also getting better, but still don't seem to be able to rival the sharpness and imaging a good portion of the RPTVs. Projectors can rival and surpass some of the RPTV offerings in picture quality and offer a small form factor, but these options most certainly come with a price.
Prior to purchasing my Hitachi, I found Toshiba, Mits and Pioneer Elite also had some excellent RP offerings. From my research, the RPs seem to allow for some of the sharpest, vivid viewing for a relatively low cost standpoint. A properly calibrated RPTV is almost impossible to beat at a relatively inexpensive price. To find a projector that rivaled some of these images were anywhere between $1000-3,000 more.
If size isn't a factor and budget can be (well, for most of us anyway...
), RPs are an excellent value. If size is a factor and cost is less of an object than getting the best picture available, projectors have come quite a long way in the past few years and likely would give you the best possible picture overall, but again, this comes with a mighty hefty price. Good luck with your decision, have fun with it!