FYI: The 5D3's battery grip is fantastic.

[TheBiles]

So much better than the one for the 7D. Much slimmer and now with a weather-sealed joystick. The batteries load from the side much like the 1D-series. Here's a full album of my hands-on.

Some important images:

The new curve that fits the hand much better:

The new way of loading batteries:

 

[jaomul]

I don't believe you. I think you should ship camera and grip to me for a few months and I'll write a more honest review