cydia stopped working and i don't really find myself using jailbroken apps that much anyways as all i use is e-mail, facebook, and the internet. it's also really annoying that all the apps i try to download require the 3.0 update. would it be safe to buy the 3.1.3 update and upgrade from my current jailbroken 2.2.1? also, will my music also delete? i switched computers and don't have any music on my current computer and none of the music i have i bought from iTunes, so it can't be recovered from there.