I have an iPod Touch 2g 8GB MB model that is currently running on OS 3.1.3 with the spirit jailbreak. I do not plan to upgrade to iOS4 anytime soon, however, if I ever encounter a problem with my jailbreak, iTunes will force me to upgrade to iOS4. Should I back up my SHSH blobs now just in case something happens? Or will I be fine because it's a 2g iTouch? If I have to back them up, which guide on this site explains backing up and using the blobs best? Thank you.