I'm from SoCal and am interested in doing Rim to Rim. It probably won't happen this year, so I plan to start looking into it this fall after we're done with the hikes we have planned for this summer are finished (we have Whitney, San G (again) and C2C left).
I did a day hike of the Grand Canyon a few years ago, back then I was just kinda along for the ride, but I believe we did South Rim (down South Kaibab trail and up the Bright Angel Trail).
The two 'barriers' for me so far have been the logistics issues (Whitney Fan's post about the shuttle helps with is) and finding someone to do it with me.
