"Mike, you're going to scare him away =D" Hope not. :-)
Final Cut Pro's way of handling the CODEC is, as Studio460 indicates is rather inelegant. It did, shortly ago anyway, transcode to an Apple CODEC and use that. I use Vegas for it's simplicity, but for our video work we have been using DVC Pro HD, a professional CODEC that, when we started, only a limited number of NLEs could edit easily. Adobe Premiere Pro was one of the better solutions for that CODEC. It doesn't hurt that I teach Adobe products. ;-)
What target the production is matters, of course. Our _Outdoors_ Channel experience (I DP a few episodes of a hunting show) over the last few years is 720p60, and PBS series (which ended a 6-year run for which I was the Associate Producer) was 1080i60, neither of which fits any of the current D7K formats, and I have no clue whether Nikon will offer a firmware update. I'm hopeful, but I'm not betting the farm.
For HD broadcast, a 1080i60,1080i50, 1080P30, 1080P25, 720p60 and 72050 would have been more useful rates. Of course, no one asked me. I'm guessing that fewer than .01% will convert their video to film, something that 1080P24 would really make sense in using.
All CMOS cameras have rolling shutters, even the Red cameras, it's how well they manage data from the sensor to the video processor. Canon does this better than Nikon right now. Even Panasonic does it better.
But shooting movies isn't shooting stills. The jello effect can be nearly eliminated if the camera or subject don't jerk around; the use of a fluid-head tripod might solve the problem altogether.
Studio460 is also right on target that the APS sensor is larger than most of the film 35mm formats, so that you can get film-y looking stuff from a APS-C camera - one _doesn't have to go to full frame_.
I'm not sure about how much shutter control one will have with the camera. _Generally_, motion picture film cameras only have one shutter speed, 1/48th of a second. The mix of aperture and shutter speed is accomplished by the _angle_ of the shutter which is a rotating disc. The disc is angled so many degrees to allow the light to hit the film for proper exposure. The time is fixed, _generally_. Undercranking_ creates fast motion, overcranking creates slowmotion, and special shutters can create special effects like the hyper-reality of _Saving Private Ryan_.
Of course, in electronic video, even in the D90 and D7K, there are no shutters. There are electronic switches that go on and off collecting data, but down to 1/24th (popular convention will call it 1/30th) of a second only - the upper limit I'd be clueless to, or you'd have under cranking, something that would be nice, but not promised nor mentioned, and if it acts like a _film camera_ 1/125 and over would cause over cranking, but again, I doubt that, too. It could, of course, put all the information in multiple frames, as to fake long time, or short time, but that wouldn't be so good either would it? I would want my camera to shoot honestly.
I do like the AVCHD CODEC. It's robust in it's color space and most NLEs can handle it. I think it's a step up from the MJEG. One of the issues I had, and it's the dummy in me, I didn't use the picture controls in the camera to neutralize the footage prior to taking the video. Since the CODEC is MJEG, picture controls influences movie output, you want less contrast in the video so you can manipulate in post. Oops.
While I sound like I'm bashing the D90, and I sort of am, it can make nice-ish video. The trouble is how limiting it is. I think Nikon can do a lot better. I'm hoping it will.
I ordered my D7K from Amazon last Friday, so I'm committed to it.