a word of warning however...backups can get funky with certain jailbreak tweaks installed. I'm not sure what causes it, and everything that causes an issue, but I can warn against the following things:
custom carrier banners will be preserved by a backup, even onto a non-jailbroken phone
hidden apps will remain hidden via backup onto a non-jailbroken phone, but with no way to install poof, you can't get them back.
My advise to people in general is that if they ever choose to go back to being non-jailbroken, they install everything they installed via cydia, then back up one more time, THEN restore