I hope someone can help me. I just got a new ipod touch 3rd gen running 3.1.2. I haven't jailbroken yet since it is still tethered, but I'm anxiously awaiting the new untethered jailbreak which will reportedly be released once the ipad 3G comes out later in April. What I want to know is should I upgrade the firmware to 3.1.3? I just read an article here
which talks about the importance of backing up the ECID and SHSH files. Apparently this can't be done for an OS earlier than 3.1.3 since Apple stops signing the old ones once they release a new one. Can I still back up 3.1.3 since 4.0 is out now? Should I upgrade to 3.1.3 to back it up? Is there anything else I need to do/not do looking ahead to jailbreaking?