Hola, I've been following this thread, and I just had a thought that would make the t4i a much better camera.
I have no idea if it's possible or if it's a reasonable idea, but I wish I could swipe the touchscreen with my thumb as my eye is in the viewfinder, as if I was changing the aperture with an aperture wheel on a non-Rebel canon. So, the touch screen would just replace an aperture wheel when I'm looking in the viewfinder and getting ready for a shot.
I've never used ML, and forgive me if this is far out of the realm of possibility. It's just an idea that I thought might help

I wanna thank you guys for doing what you're doing, we all appreciate it!