I've got a 2.5 year old Macbook Pro with a 5400RPM drive in it. Since installing iLife '09, I can't help but notice that my programs seem to take a long, long time to start up. Even after having just reformatted the thing and reinstalling Leopard, iPhoto '09 takes forever to load in the initial set of Faces or Places, and iMovie has a lot of trouble capturing a full HD video at full speed (often times it'll capture at 1/8 speed) and has trouble playing the captured video back in preview. Note, though, that the iMovie captures are going on on an external 7200RPM Firewire 400 drive. All that said, I've been eyeing this Seagate Momentus 7200.4 500GB drive for a few days now, and I'm wondering if an upgrade to it (realizing that it will void the little bit of AppleCare I have left) would be worth the investment. In the Fall or early next year (whenever Apple releases i7 or i5-based Macs) I'm going to upgrade the system, but I haven't decided on whether to get an iMac or another Macbook Pro. This will help me determine if the hard drive is the weakest link in this equation. The hard drives in the new 15" models are user replaceable in warranty, aren't they?