The new firmware for the 5D Mark II will arrive the week of March 17, 2010. This seems to be close to the NAB show.
The information briefly appeared on the Canon UK web site, it’s now gone.
Live Histogram for Video
Sound Level Control
No word on 60fps yet.
I’ve also heard there may be sound level meters, count this feature as a CR2 rumor.
More info on the subject to come.