Well, here's the thing.
I first saw Karl Urban on Xena, playing Caesar-Julius-Caesar (how he always introduced himself...hey, it was a campy show, especially at the beginning) and (gulp) Cupid. When he played Eomer in Lord of the Rings, that was marginally okay, because he didn't look like Caesar.
But...the pictures...the new pictures.
Good Lord, it's McCoy-Leonard-McCoy.
Allow me to explain graphically.
2. does not equal
Now, other actors have gotten past this barrier. For instance, in no universe anywhere does Bester = Chekov even remotely compute. And yet, I never got past Archer = Sam Beckett either.
That said, Zachary Quinto bears an eerie resemblance to a young Leonard Nimoy.
In short: the jury is still out.