Just got back from Puerto Rico and found my new 2TB drive waiting for me. Popped it in, partitioned it and copied nearly 1TB of files to it overnight. What I forgot to do was to tell Time Machine to exclude the new drive from it's backups so now the remaining space on my DROBO (which is where Time Machine backs up) took a huge hit. Figured I'd delete a bunch of old backups (some from 2008) but couldn't remember how to do it properly. Couple of searches turned this up so I thought I'd share it with you guys. You can't simply go into Finder and delete from there... it screws up everything.
http://www.vimeo.com/3268578
http://www.vimeo.com/3268578