Title says it all. In my opinion, I might as well because I could finally have a use for my iPod Touch (handoff and continuity)
I did for iOS 6 -> iOS 7, but iOS 8, while great, isn't as much of a leap as the prior update was.
7.1.2 jailbroken is silky smooth and I love it. Plus, most of iOS 8 features are still being finalized (handoff) or really need the iWatch to be a showstopper (Healthbook).