Carlos Pacheco actually went the distance in trying to give Marvel a psuedo-reboot notion during his run on the Fantastic Four. Reed activated the Ultimate Nullifer, and wiped out the universe for about a second. When it phased back in, he clearly stated that certain aspects of history had changed. I've always believe this was Marvel's half-assed way of giving an explanation to the 'forward-slide' of the timeline scale.
Nowadays, Ben Grimm was a pilot in the first Gulf War, and Tony was indeed injured in the Middle East. As far as Peter on a Late Night show, I'd imagine it's Jay Leno or Conan O'Brien now...
