Like Mike had stated, the RS45 in the same price range has at least 5 times the native contrast ratio of the Panny 7000. I know that the Panny 4000 had a measured NCR of 6000:1. How much better the new 7000 model may be as far as NCR level? we don't really know. But I seriously doubt it will measure above 10,000:1. So bottom line, the JVC will produce a better 2D picture with the whitest whites, blackest blacks, and everything else in between on the same frame.
BUT I will play the devil's advocate here, and will tell you that the Panasonic AE7000 will likely have the smoother picture because of their ultra fast 240/480hz FI compared to the JVC which will more likely be just a slightly improved 120HZ FI over last year's models. So if you care for a more true film like picture and amazingly inky black levels and super high native contrast levels, go with the JVC. If you want a shiny ultra smooth motion go with the Panny.
The one thing I always liked about the JVC is that what you see, as far as specs, is what you end up getting (minus the obvious unpredicted lamp defects). But JVC's marketed lumens and NCR measurements are always right on with what the reviews conclude, give or take 10%. On the other hand, professional reviewers have in the past ripped into the highly inflated and purely marketed dynamic contrast ratio and lumens levels that manufacturers such as Epson had greatly exaggerated.
There is a reason JVC is such a great seller here, not because AVS sales continously recommends them, but it's because AVS members are more satisified with JVC's quality products, and now more than ever with the much lower street pricing competing head to head with the entry level 3D projectors from the likes of Epsons and Pannys.
Yes I said Pannys.