So, since I'm a new owner of a Momentus XT I was wondering if anyone had any insight on FileVault 2 on Lion. Will doing a full disc encryption with FV2 cause any negative performance with my XT? I know that just by design FV2 will cause disc slowdown, but will it cause any issues, specificially, with the 4GB SSD portion of the drive? Since everything is encrypted, does it make it so the XT won't be able to tell what I use most often to properly cache it? Or will it still store the encrypted file so that when it's unencrypted it will still be on the SSD portion? Anyone have any insight before I activate this? Thanks!