Yes, and on top of that, I have yet to see an HD-SDI monitor that doesn't offer loop-through, so you can loop out of your onboard monitor for a director's monitor. Actually, the Blackmagic converter has two HD-SDI outputs so you would have 3 possible outputs with that setup.

For Lynne, the 1D Mk. IV has the exact same HD video recording capabilities as the 7D (with the exception of superior low-light capability, of course). So you could review all of the pros and cons which have been previously discussed rather heavily around here regarding the 7D and the nearly similar (in terms of HD recording) 5D Mk. II and use them to formulate an accurate opinion of the 1D Mk. IV. Hope this helps,

I'm still waiting for somebody to do the strobe test on the 7D in 1080 and 720 modes so we can get an accurate measure of its rolling shutter. From the 1D4 video that I've seen, the rolling shutter effect is significantly less than the 5D2 and 7D. I'd really love to get the scan speed numbers from that puppy!

The most important drawback, IMHO, is that it does not (presently) run Magic Lantern.

I'm hopeful that the low light performance is improved as well, but I haven't seen any raw images from it yet, so I don't know yet. The 5D2 starts with a big size advantage (1.7X more light gathering area), which gives it a 2/3 stop advantage in low light. Hopefully the 1D4 technology is a full stop improvement, enough to take the low light crown from the 5D2.

The DOF control is nice, more than the 7D but not as much as the 5D2. If you never shoot wide angle, the lens selection is good. But if you want wides and ultrawides, the options are worse than the 7D and 5D2. Canon makes lenses for spoons (1.6X) and they make lenses for forks (FF), but they don't make any for sporks (1.3X). For example, to get the same angle of view as the 10-22, Canon would have to make a 13-29mm.

Update on the Marshall monitor issue I mentioned earlier: it seems that it was an isolated issue with the particular monitor in hand. Marshall was able and ready to fix it and did so within a business day.

I will be looking at their transflective 6.5" HD-SDI model as the onboard monitor for my 1D/5D setup. Interested to see whether it will be viewable enough under all daylight conditions to work without a hood. This would replace the need to use a loupe on the camera's viewfinder, resulting in a more streamlined handheld configuration and higher resolution to judge focus.

1Dmk4 Footage From Sydney New Years Eve 2009
 

It was interesting to read Michael's thoughts about the quality of footage he got from the 1Dmk4 compared to the 5D Mk2: