I just recalibrated my Touch ID in iOS 8 and got this screen after the process. The language is Norwegian, but you can clearly see the iPad reference...
I think it's obvious already that it's coming with the expansion of Touch ID authentication into third-party apps and experiences. It won't make sense to leave the power of this out of the iPad experience for a moment longer than necessary.
Why would it say iPad? I'm guessing a bug. Looks like the OP was doing this on his 5s and Apple probably forgot to remove the frame work from iOS 8. Best guy is it's being beta tested right now.
Yeah! Now I know it's worth the wait for the new one. I really wanted TouchID on my iPad.