Photography is just a hobby and I usually use center-point and recompose.
I currently use a 5D2 coming from a 60D, and have been satisfied with the AF capability of the 5D2 and the 60D. However, please note that I am not a PRO but an ordinary guy taking photos of friends, family and a few nature/landscape scenes.
If wedding photography is important, why not go to other sites (like flickr, professional wedding photographer site, etc) so you'll be able to answer the questions of:
What camera body do professional wedding photgraphers use as their camera bodies? 5D2, D700, other camera bodies/brands?
What's the IQ of actual wedding photos taken by the 5D2, D700 or other models/brands? Is the camera body you are considering able to output photos to your satisfaction?
Of course, the most important factor would be the person behind the camera and the camera body is just a tool which has limitations/capabilities, and it is up to the photographer to optimize the use of his equipment.