Speaking from a videographer's pov, DSLR movie modes are really fun, and the prospects are exciting, but there are problems abound that limit their usefulness as serious movie recording devices:
Ergonomics: it would have been ergonomically difficult to film properly and stably when you hold a lump of camera in front of you. It's fun at first, good for trips and such, but gets shaky and hand straining if you want to do this the whole day - EVF helps here and it puts the camera back up to someone's eyes, and if anybody's going to do it, maybe Panasonic can with an upgraded G1 or a successor model (I'm an EVF guy, but will use LV when needed).
Stripped down Movie Modes on Entry Level DSLRs:
720p - (D90, D5000)
20FPS - 500D
Shallow DOF presents problems during usage/ AF & MF tracking with telephoto focal lengths and large apertures:
DOF, large sensors available at a lower price with DSLR lenses - This is a hugely exciting prospect, but can you Dolly and pan while you focus and zoom?
AF is rather slow and sluggish on current implementations, factored in the larger sensor and longer lenses, you are left with a much shallower DOF, it means a longer wait for AF to correct itself, it negates the benefits of large sensor and large lens recordings and limits you to smaller aperture kit lenses that offers a large enough DOF for realistic video recording usage.
AF motor noise - goes straight into the built in microphones - and excludes a whole lot of lenses and limits you to AF-S/USM lenses if you want AF to function during video recording.
Lack of External Audio Input - 500D, D90, and D5000 as up to this moment has no external Audio Input. Only the more expensive 5DMK2 has external Mic input.
Lack of mounted continuous light source accessories that has an option to draw power straight off the hot shoe.
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Video on DSLR is fun, but gives you a harder time and be more of a hassle to work with. If people really wanted video, get a camcorder.