re: Ipad Air, Mini, or wait for the new one?

The only thing I've really seen rumored of significance for the iPads is touchID. There's also been chatter about an anti-reflective screen that works better in bright light/daylight. You can probably also expect the standard improvement in build and chip speed.

TouchID can be a compelling feature, never having to enter your AppleID or lock screen passcode, but I'm not sure it's more compelling than the discounts you'll see on last year's model when they start the clearance sales a month or 2 before the new release.