Just updated from 4.1 to 5.0.1 using a JB custom ipsw and used OpenBackup to back up all my settings and packages. I didn't see a thread about it here, so I thought I'd give it a shoutout. It worked great! There was a little tweaking that needed to happen after I ran it, due to the differences between iOS 4 and 5 (mostly little LockInfo things), but it still saved me a ton of time! Note - I'm not affiliated with the author or anything...I actually have no idea who wrote this tool. Just thought it should get a little publicity.