CS5 -- Core 2 Duo only?
 

I assume they mean you need a minimum of a Core 2 Duo. I'd like to use a Core 2 Quad or i7. But the language seems to suggest you need a Core 2 Duo specifically: system requirements | Adobe Premiere Pro CS5

That can't possibly be right, can it?

Nope - I'll bet on that - it's minimal processor.
An i7 will do. I have just ordered a new mobo with a 6 core i7 - my i7 works perfect with CS4.