yeah, it's already been done, and it's pretty good considering they used two GoPros and not some fancy specialized camera. Check it out:http://www.uscsnowsports.org/2010/02/3d-edit/
Only Red/Blue if you have the right hardware. For all the 3D stuff, the source files are the same, you just render the clips differently. To get 3D to the masses at this point it still has to be done in red/blue unless you are able to do special screenings at 3D capable theaters which is nearly impossible.
Here's ours: