Jailbreak 101 Episode 5 – 3.0.1 and APTBackup
3.0.1 was released recently and closes up an exploit where someone could hack into your device by sending a simple text message. I highly recommend you update your firmware to fix this possible exploit. Here are instructions on how to re-jailbreak one you update your device. I have also included instructions on how to backup your cydia apps and restore them if and when you decide to re-jailbreak your device.