Marc was kind enough to upload a photo of his system.
It's about $525 at B & H. I noticed it specifically because the biggest problem I have found with shooting video on the 5 D is the fact that there is no way to monitor the sound and he was shooting with earphones plugged in. I was intrigued enough to hang out and wait till he was done shooting so I could ask him about it.
The system is still limited by the fact that the Mark II uses a relatively unshielded mini jack (which can be affected by certain ambient frequencies, like fluorescent lights), but it's by far the slickest rig I've seen and I'll be buying one as soon as I have a project to justify the expense.
The new manual firmware (available from the Canon website) makes the camera a much more viable video camera. I've been shooting an experimental film with it this summer and took some of my footage over to the guys at the NYU SCPS video department who were pretty blown away by the quality of the image and the ability to shoot video on a full chip camera.
The best part is that all of my beloved, and fast, Nikon primes that have been sitting in my closet for the past 5 years now have a new mission as video lenses thanks to a great lens adapter I found out of Hong Kong that is is cheap (about $ 25) and has the necessary electrical contacts to auto confirm focus.
The final addition comes from Tisch alumni Clayton Burkhart who showed me his very nice Zacuto loupe which attaches to the back of the live view screen and makes it a viable electronic viewfinder that is better than anything I have used on a dedicated (video only) camera. I didn't spring for the $ 425 Zacuto (which is much nicer) but went for an $140 Hoodman loupe which is functionally just as good but not nearly as comfortable or nicely made as Clayton's Zacuto.
By the way, the most recent video entry on Ceci's blog (Butterfinger Ice Cream) was shot entirely on a 5D with the crappy little mike I carry around in my camera bag that it just clipped onto my lens hood. Even with youtube compression it looks pretty good in HD. If anyone has any really good settings for uploading to youtube or vimeo I'd love to hear from you.