Hello all! I know the topic of which hard drive to put into a macbook has been wildly debated and has been the topic of numerous posts... BUT... none have quite answered my questions... I recently found out that western digital is making 750GB and 1TB 2.5'' drives. The only problem is they are 12.5mm drives. Will this fit into a 2009 aluminum macbook? From what I have read, the only size that fits the macbook is the 9mm (9.5?) drives. So that leaves me with 2 options for a large capacity drive... Seagate 7200rpm 500GB drive or Western Digital 5400rpm 500GB drive I'm looking to purchase through Best Buy. The prices right now are $129 for the seagate 7200rpm and $89 for the western digital 5400rpm. But, the money is not an issue for me. The main reason I want to upgrade to a larger drive is because right now I have a stock 250GB. I recently tried to partition the drive using bootcamp and disk utility, but got an error saying that files could not be moved. Basically there is not enough continuous space left on my hard drive to format it. I recently transferred most of my data to my external drive in hopes that this would free up some continuous space, but it didn't work. I currently have ~95GB free. I also tried iDefrag in on-line mode but after defragmentation, I was still unable to partition the drive. Believe me, its been quite frustrating! Also, the western digital 500GB drive is in stock at nearly every Best Buy that is close to me, but I would have to drive an hour and a half to pick up the seagate 500GB drive.