The next generation Penryn processors for notebooks will ship at higher speeds than the current Core 2 Duo Merom based CPUs and they will be just slightly better than Merom on the battery.

We had a chance to see 2.8Ghz clocked Penryn based CPU and it does run faster than the 2.6 based Merom CPU. Penryn can encode Video slightly faster than the previous generation.

Intel's representatives have confirmed that Penryn won't be a miracle for your battery but that will indeed offer higher clock and better dissipation clock to clock.