I've recently installed the JVC RS50 and all I can say is that it is, flat out, the best projector I've seen out of the box, ever.
There are some real questions which haven't been addressed or touched upon at this point.
1. What is your theater setup? Dedicated? Dark walls? Screen size? Viewing distance?
Your budget is obviously significant, so it may be worth considering that a dual screen setup makes more sense than spending twice as much on a projector which delivers little more. A high gain (2.0+) screen for 3D, then a minimal gain for 2D.
Home theater asks for about 13-18 lumens per square foot of screen space. On a 120" diagonal screen, that's about 775 lumens required (43' square) on a 1.0 screen that size. Double the gain (2.0) and you need less than 400 lumens for the same perceived brightness.
The JVC does not use an iris system, but produces one of the best black levels in the world by using good technology. LCoS is a very good solution for front projection and is what Epson will be using for their forthcoming 3D projectors later this year (hopefully).
Nice enough, the new Mits. projector just got a review up today...
http://www.projectorcentral.com/mitsubishi_hc9000d_projector_review.htm
There aren't enough reviews of the JVC out there right now to draw solid conclusions, but historically the JVCs have been class leading for 2D. Like, serious class leading.
Top shelf projectors: Sim2, Digital Projection, Projection Design, and Runco all add a small (and questionable) addition of value to the home theater experience. Unlike your Pioneer Elite, which provided a noticable black level jump and performance increase across the board compared to almost all other technologies out there, and has yet to be matched, the projectors coming out are just constantly getting better and the big boy companies, Epson, JVC, Mitsubishi, and others are just constantly improving.
I will say, that while I like DP projectors, and they are starting to offer some pretty value concious models, I'm not sure if they support frame packed Blu-ray 3D support since they only have HDMI 1.3a inputs on their Cine projector. This is a bit of a quirk with some projectors which advertise as 3D, but don't actually support Blu-ray 3D, just some of the other flavors.