The D90 allows you to select the aperture (from wide open to f/8) prior to commencing, then it handles the adjusting of ISO and shutter speed automatically as needed to maintain video brightness as lighting conditions change during recording. To disable automatic exposure adjustment, it’s possible to lock exposure prior to beginning the recording.
Sounds a bit like the HV20/30 dance to me, where you’re always aiming the thing at a light trying to lock it into 1/48th shutter. Stock up on ND if you want that filmic shutter and shallow DOF at the same time in daylight! Still, if this is true, you can lock down your auto settings and, perhaps somewhat clunkily, explicitly set a shutter speed.
Of course, unlike Rob, I view the lack of automatic white balance and as a good thing. I’m also baffled by his desire for a digital zoom. I guess what stills folks want from a video camera is different than what film folks want from a stills camera that, uhm, shoots video.
The boards are positively buzzing about this (dvxuser, scarletuser, dvinfo, hv20.com, Rebel Café). There’s some clarification, some idolizing, some bashing, and enough hypothetical confusion that I’m happy to refrain from any further speculation of my own. We’ll see real sample movies and detailed hands-on reviews soon enough.