A jump in performance
Multitouch aside, you're more likely to be considering one of these new notebooks if you're using one of the first-generation MacBook Pros, or an even older PowerBook. In that case, you're in for a serious speed boost. That's in large part because of Apple's 2006 shift from PowerPC processors to Intel chips -- the jump from PowerPC to Intel represented a much larger speed jump than the move from Core Duo to Core 2 Duo chips, though the improvement is still noticeable.
I don't have an older MacBook Pro or PowerBook to test this unit against, but the speed numbers put together by Apple should give you an idea of the difference. Using Photoshop CS3 to apply 45 common filters to a 120MB file, the new MacBook Pro is more than three times faster than the last generation PowerBook with a 1.67-GHz G4 chip; and it's 50 per cent faster than performing the same task on a MacBook Pro with a 2.16-GHz Core Duo processor. As always, your mileage may vary.
As for the new Penryn processors in the new models, they're manufactured using the 45nm process, meaning they should run a little cooler than their predecessors and squeeze out a bit more battery life. They also offer differing levels of Level 2 cache memory, which can offer a small speed boost. The 2.4-GHz chip has 3MB of Level 2 cache; the faster chips have 6MB of Level 2 cache.
I noted little difference in the performance of the new models and my last-generation MacBook Pro. I also never once heard the fans come on during routine use or even when pushing the processor with some heavy Photoshop use. Battery life was on par with previous models.
With its latest revision to the MacBook Pro line, Apple has taken what was already a solid laptop and added a few new tricks that should keep buyers coming back for more. No one who's bought a MacBook Pro in the last year should feel any buyer's remorse; their laptops stack up fine against the new generation. But anyone with a MacBook Pro that dates back to 2006, or who's still clinging to a PowerBook, would do well to check out the latest Apple has to offer -- especially because the multitouch features could come in handy in a pinch.