Google allow Android users to backup their apps, settings, passwords om their Google account and it restores everything back to how it was when you do a full reset of your phone. However, it never backups up your call logs. To most of you, this may not seems of any importance, but for some, it does.
Android keeps a record of your last 500 calls. There is an app available on the Android Market to help backup and restore your call logs on another phone or after a full reset.