I just spent today helping demo at MacWorld, and the company I work with just played the first party ever (according to the Rane management) with Video SSL.

Oh my my.

Simple run of features: Two "channels", like regular Serato, but capable of playing videos at the same time. They can be layered and effected by the other. You can take the video of ONE file and the audio of ANOTHER and play them TOGETHER on the same channel. So Channel one can play a montage of fight scenes from The Matrix over a Deadmau5 track and Channel two can play ambient shapes over a Joel Armstrong tune. 

Bad news: Right now, it only works with one (MIDI capable) mixer, and it's not cheap.  http://www.rane.com/ttm57sl.html

We used to use DVJs for our visual mixes. Now we're moving toward this.  And it's waaay cheaper than a pair of DVJS ($7000) plus a video mixer (~$1000), even if you include a beefy computer and bulky/fast hard drive to go with it.

It's basically SSL 1.8. The video feature is just a plug-in.

The reason the Rane mixer is the only one compatible is because it has a MIDI value assigned to every control, basically.  I betcha they allow seperate MIDI controllers or other MIDI-capable ones (DJM-800) eventually.