iPad 4 or iPad Mini worth it despite rumors of new ones in two months?

Hey Verge! I need some advice from you guys, and while it may seem like the usual "is it worth it" post that comes up every new product release, it would still be nice to get some input towards this 400-700$ purchase!

I've been considering buying one of iPad 4 or iPad Mini, at 32 GBs of storage, but I've been holding off/hesitating since the increasing rumors of new models coming in two months. That said, I'm most concerned about the longevity of the product I might get. Specifically, I'm REALLY concerned about the length of which the iPad I buy is supported by Apple in terms of getting FULL iOS updates.

That said, should I even buy an iPad 4/mini now if I want the longest possible product cycle from Apple (iOS-update wise, remember)? And if I should, then which one should I get? The iPad Mini's price attracts me, especially since I'm opting for 32GBs of storage, but the iPad 4 seems more future-proof.

I know that the iPad Mini has an outdated processor, meaning it would be "obsolete" soon, but after trying it out in stores, it seems...really fast, when I compare it to my experiences with the iPad 2 in the past. I'm not really CRAZY for retina, but it would be nice to have - in fact, looking at the pixel density of the mini in store didn't seem all that bad for a 7.9'' screen.

And in case anyone's wondering, I'm planning to buy one for heavy use in school - reading textbooks, taking notes whenever possible, portability, battery life, and the integration I'd get with my iphone.

Thanks in advance guys~