Sorry, just had to post to this message. Its my first post every, so please be nice. I am a Sony snob, so thats the only brand I can tell you about. I have a Sony 8mm, a Sony digital 8mm and a Sony miniDV. The Sony digital 8mm does a good job, but the miniDV produces a far better picture! With the DV you get digital video that you can transfer to your computer and then to a DVD or CD or video tape without loosing any quality. When I see videos of my oldest I cringe and the quality compared to the DV. The digital cameras are also a lot smaller then the 8mm cameras (and lighter) so its easier to take somewhere like Disney.
Price wise the only difference between the cheap and expensive camera are the options or the mega pixels of the still picture camera. The quality of the video you get on the cheap camera is the same as the quality on the expensive camera. Since you already have a digital camera, get the cheaper digital video camera.
I hope this makes since. This is a passion of mine (I have a degree in it) and I would highly recommend the miniDV digital video cameras over the digital 8mm. You would be amazed at how clear the picture is. (Its like comparing an old video tape to an old DVD, whats going to look better).