Apple's yearly developer conference should see iOS 8, OS X 10.10, and likely some hardware.
MacBook Pro Targeted 2.8GHz Core i7 Processors Due Later This Year
A newly leaked Intel processor roadmap reveals that the company will be releasing a speed-bumped Core i7 processor this fall. The upcoming Core i7-640M will run at a base frequency of 2.8GHz with "turbo boost" speeds up to 3.46GHz. This new processor draws the same power as the current MacBook Pro processors so should be a natural upgrade for Apple.
The MacBook Pro presently tops out at 2.66GHz with the Core i7 processor. It is available in both 15" and 17" models. Apple last updated the MacBook Pro this past April. It's unlikely that Apple will refresh the whole lineup this fall, but could offer the new processor as a build-to-order option. They've done these quiet upgrades in the recent past with the the Mac Pro.