Very early on in Apple's history, there was a time when Steve wasn't the world's greatest presenter. Sure, he had charisma, but I've seen videos when he came across as nervous. But Tim has no comparisons to him in his prime, but that's okay, since no one else really does, either. I think Forstall and Schiller do a pretty good job, and I'd love to see Jonny I've actually come out on stage.
But mark my words...
THERE IS NOTHING WRONG WITH TIM'S ACCENT, and don't you even suggest it!