I'm not quite sure what your point is, other than to be argumentative.
Touch screens are miserable interfaces outside of a very few select devices, and even then they're more for aesthetics than anything else.
Swivel screens brought something to the party. Touch screens are bringing something too, but it's spiked and may leave you in a coma.
My point is that posts whining about Canon adding new tech to DSLRs are just old, tired and annoying.
I am not especially fond of touch screens, and probably would not use it much if I owned a T4i. But that's just me. Lots of people (younger ones, especially, it seems) consider a touch screen to be standard on most any device or gadget.
Plus, it can actually be useful for choosing a focus point. Not saying a pro sports shooter would use that, but it could have some benefit for some people. And even if it is not, it probably won't "ruin everything".