Hi Flanders,
As for the HD2 chips, some say we'll be seeing better blacks/contrast...others are not so sure. In any case, we'll see sometime likely this fall.
I chose the Marantz over the Sharp. I demo'd the Sharp standalone, with a Faroudja NRS and a Runco PFP (both standalone deinterlacers/scalers). I also demo'd the Marantz. The Sharp improved noticeably (to my eyes) with the outboard scalers. The NRS was the (slight) better of the 2. The improvement was mostly in getting rid of jaggies on the edges of objects. It was noticeable to others in the room as well.
Standalone, you could see jaggies on the Sharp from about 1.5 screen widths away. WIth the processors, you could get much closer - even up to .5 screen widths away before seeing any jaggies, and even then they weren't as bad as the ones the Sharp produced.
Also, the worse the source the bigger the impact of the better outboard scalers. Good progressive DVDs look quite nice when fed directly into the Sharp. However, SD cable/satellite, VCRs are much improved with the outboard scalers.
So why'd I buy the Marantz? It basically has the primary processing chips of the Faroudja NRS built into it. It has a sealed optical path (the Sharp does not) and in the demos I saw produced an outstanding, filmlike picture.
However, as you've probably read the Marantz has had some problems of its own, particularly a pesky flicker every now and then. We've recently been directed by Dan Miller of Marantz to take our PJs to our dealers to be fixed. That word came out in the last couple days. Dan is still in the special guests forum and there's more info there.
Hope this helps,
Tony