"digital video" means that the timecode is absolute and recorded "digitally", which allows a computer to control the camera and digitize/capture footage with a computerized "to-the-frame" accuracy that was not available on ANALOG video.
Since so many video cameras are now tapeless, recording to solid state like P2, SD or CF cards, along with the new look of shallow depth of field from DSLRs, the vogue term for this is simply "digital" instead of saying "digital video". The word "video" connotated something sub-par or an aesthetic look that was not preferred, especially by filmmakers. So the press is now calling it "digital". "Video" also generally meant some form of tape, albeit inaccurately. I think it's a new marketing term to make the DSLR looking video more acceptable and losing the word "video" from the lexicon to legitimize the movement.
Technically, you can have digital video, or just video. You can now have digital with no tape at all.
It's almost a "who's on first" routine...