I think all this discussion of having swappable external SATA drives is really great, especially for the really heavy users out there. I should think ultimately you would want to fill up a drive, disconnect it, and then back up its contents somewhere. Has anyone tried to get Windows/Linux to recognize these drives? Backing up the contents from the file system level would be a breeze. However going "beneath" the file system level and doing a backup at the sector level is probably unworkable.
Alternatively, just keeping multiple drives and sorting them in some fashion (for example by year recorded, or by the theme of what is recorded) is certainly workable.
(Of course little ol' me won't do anywhere near the amount of recording to justify all this effort!)