It will be fantastic to have a real support of anamorphic lenses.
In 550D you Can shot in 4:3 crop mode at 640x480. It's fantastic if you could shot 1920x1080 but in 4:3. So, with a 2X lens, you have a real 2.35:1 video without any cropping. Wow!
Oh yea, this is my dream too.
Customizable frame aspect without crop. 4:3 pixel aspect on 1920x1080 it's not possible without distortion loss, only at 1920x1440 or 1440x1080. But the 2nd option we can do now with crop, don't need ML. So need some information
what is the maximum resolution that with work on 5Dmk2, and possible to change custom video aspect and how to combinate them.
The point is that there are 2073600 pixels and lose none of it, but we want to vary the aspect ratio from 16:9 to any size. 
It's my video, taken with 2x. I think it's nice, but too wide for common displays. It's 3,55:1 aspect but it would look nicer on 2,35:1.
