I bought a 13" unibody MacBook less than 2 months ago (less than a week before it would've been a 13" MBP). Anyway, now I'm wanting to sell the 13" and buy a 15". I realize I can get my data transferred from the 13" to the 15" and reformat it, but I'm overly cautious and don't want any personal information getting out so I would like to just switch the hard drives. Are there any hardware compatibility issues with doing this? Also, what about software registration issues (i.e. MS Office, Apple Care plan, etc.)? First post; sorry if this has been discussed. I didn't see anything like it. Thanks dudes!