Originally Posted by sherwood

Core i7 is a completely new architecture. The "turbo boost" you're referring to is actually real-time processor frequency scaling IIRC it's also core-independent based upon requirements and temperature among other things with the maximum boost only being applied to one core. [in this case I believe it's a 10*133Mhz boost over 1.7GHz for appx. 3.0GHz on Core 1]

Performance gains, as usual, will depend on your application. If you are looking for a general purpose computer I'd be inclined to suggest Core-2 just for the bang/buck ratio. Core-2 is going to be phased out in favor of processors based on i7 and i5 in the next few months. But depending on where the market goes, and how the changes are implemented YMMV