Good review, Justin. In a studio setting I found the 60D/7D optical triggers worked fine, but yes, they were nightmares outside. When I went to full frame I purchased the Yongnuo 622s and they have worked well for me. Glad that Canon is stepping up the technology, though.
I wonder if they (through firmware) will allow for flash control with the 600EX-RT using the 6D's wireless system. I would hope that, at minumum, future bodies would have that master control built in. It's not just the expense of additional components; it is the awkwardness of adding more components to the camera body when often what you need is to just shoot (without more and more weight!)