I've been thinking about how much a camcorder body is worth vs. a DSLR ever since Sony released details about its NEX-VG10 camcorder last week. The NEX-VG10 is essentially a NEX-5 with a camcorder body and updated firmware, for $1,200 more ($1,999 for the NEX-VG10 vs. $800 for the NEX-5 with the same lens.) Leaving the firmware aside for now, is there really a $1,200 difference between the two cameras?
DSLRs don't have the proper ergonomics for video. Still cameras are designed to be held only when a photographer is framing and shooting an image or a series of images, while camcorders are designed to be held at the eye for a long time. To compensate for DSLR ergonomics, companies like Zacuto and Redrock Micro have come up with eyepieces that fit over the cameras' LCD displays and a variety of mounting hardware that makes its easier to hold a DSLR at the eye for a long period of time.
Taking Zacuto as an example, a Zacuto Z-Finder Jr. lists for $265, and a Target Shooter, which is the company's least-expensive DSLR mounting solution, is $475. You're also going to need some kind of audio recording solution; at the bottom of the price range, you could probably get away with Zoom's $99 H1, although most people will go with something like the H4n for $299 to get its dual XLR inputs. So, to bring the NEX-5 up to the NEX-VG10 in handling and audio capability will cost from $839 to $1039. And, you still wouldn't have the updated firmware that supports manual controls and a higher AVCHD bit rate.
Once you put it into perspective, the $1,200 premium that Sony is charging for the NEX-VG10 really isn't that much of a premium. The bigger question is whether you'd want to use the NEX-VG10 at all, when you can get DSLRs from Canon that are much more flexible and have a much wider range of lens options, or from Panasonic with third-party firmware that blow away the image quality of the NEX-VG10.
I believe that the NEX-VG10 is going to find a market, and it's probably going to be quite successful, but more serious videographers and filmmakers will stick with the Canon and Panasonic DSLRs, even if they need third-party hardware and firmware to work well as camcorders. However, I also believe that the NEX-VG10 and Panasonic's forthcoming AG-AF100 are the first entries in an entirely new class of camcorders that integrate DSLR imagers, electronics and interchangeable lenses into camcorder bodies. There may be new entries as soon as IBC in September, and there's certainly going to be more at CES in January and NAB next April. At that point, you won't have to trade off form factor for capability as you will with the NEX-VG10.