Just to add my two cents here... just back from CES and had the following experiences/opinions:
The Toshiba TDPMT700 looks very impressive with HD material. With 480 material (i.e. DVD), however, it didn't look so good but this might have been for other reasons. With Faroudja processing, scaling from DVD shouldn't be an issue. It's doesn't have optical lens shift, or any other extra features, but the PQ with HD material looked very very good. Toshiba was quoting a street price of $3500.
The Sharp XV-Z2000 also looks very good (much better than the 12000 did in the Sharp theater--the bigger projector was having problems). To the extent one can compare from one demo theater to another, I would say it's very much in the same league as the Toshiba. It carries a higher retail price, however, and I'm not sure there are any compelling reasons to choose it over the Toshiba unless the Toshiba really does have a scaling issue with DVDs?
The new BenQ PE7700 looked pretty bad. Lots of video noise, some contrast problems and other issues. It would have to be A LOT cheaper than the above competitors, IMHO, to be in the running. It's possible, of course, their own theater and set up was having problems, but on a variety of material, it really didn't look that great.
The HS51 with Sony's new "black screen" was impressive, but not in the same league as the Toshiba or Sharp. The screen also only comes in one size (80") and is expensive at $2000.
In this price category, the new Toshiba, Sharp and BenQ were really the only players at the show. Given all the DLP 1080p RPTVs on display everywhere (many of which cost little more than last year's 720p version), it's my guess the manufactures are reluctant to put much R&D into 720p projectors. There were, of course, some new higher-end DLP projectors, but many (most?) were just slightly refined (i.e. DarkChip) versions of last year's model.
Talking with the TI projector specialist, he indicated it will be roughly a year before we see many 1080p DLP projectors on the market. He argued the manufactures all want to go after the high-volume sales first (i.e. RPTV) but I would think the higher margin projector business would also be attractive? Anyway, it will be interesting to see if that holds true (roughly a year for any real 1080p DLP projector selection) and where the prices end up. Personally, I strongly suspect you'll be able to buy a nice sub $4k 1080p DLP projector in roughly a year given the prices of the current 1080p DLP RPTVs.