EV is a meaningless concept in manual mode. Yes you can map EV to the 5D but not shutter speed.
A few of us are finding it beeps but doesnt change anything when tested.
So don't use manual mode right now; As far as I can tell the wheel will only do aperture. If you set A priority you can sort of half-bake shutter control with the EV shortcut using the wheel to maintain the aperture.
EDIT: I didn't think to try it when I had the opportunity, but is there a C button setting that toggles the wheel mode? I think the mavic pro had something like this, but my M2P hasn't shipped yet so I can't check :S
You can change shutter in manual but you have to swipe through it in the menus which isnt slick if you're trying to adjust on the fly and thats the issue.