I think the point is Apple prefers the 13" Macbook pro having the more powerful NVIDIA integrated GPU over the iX Intel Core CPUs's Intel HD integrate GPU.
Re:New Core i5/i7 MacBook Pros released
by OrangeGuutan on Tuesday April 13, 2010 @09:24PM
(#1263872)
Not to be snarky, but, we know :)
"We chose killer graphics plus 10 hour battery life over a very small CPU speed increase. Users will see far more performance boost from the speedy graphics" (Steve Jobs).
Step 1: Release Core 2 Duo
Step 2: Release Core 2 Duo now that they're practically free
Step 3: Profit.