I was wondering, and haven't been able to find any information, about which HDDs Apple is using in the new uMBPs. I'm about to order a 15", and I'm trying to decide between the 500GB HDD in 5400 RPM or 7200 RPM. Is the 7200 RPM a Seagate Momentus 7200.4? I'm not aware of any other 500 GB 2.5" drives at 7200, but maybe there's something I've missed. And what about the 5400? Since some reviews have suggested that the 7200.4 doesn't really offer much in the way of performance upgrades, do people think it is worth the extra noise and heat to do the BTO option for the 7200 RPM?