Fashion is unpredictable, especially for someone like me who is completely clueless about it. For example, when I got a pair of glasses with thick black rims in the mid 00s, I worried that people would think I looked dorky. Fast forward nearly a decade later, and they're all the rage.
Other trends, however, I think I can better predict:
I think that the fandoms of shows like My Little Pony: Friendship is Magic and Adventure Time could be the precursors to an animation renaissance, where animators realize that there is a market for adults who enjoy cartoons - and I don't mean mindless raunchy crap like Family Guy or South Park, but stories with likable characters and a good plot. And because of this realization, American animators will step up their game and start making quality cartoons aimed at older audiences. Cartoons with comparable content and themes (though not necessarily the same artistic style) as anime. For example, an American cartoon that turns common children's show tropes on its head by going grimdark like Evangelion and Madoka Magica did for anime.
...Okay, so this may or may not be a very good prediction. It's mostly just wishful thinking on my part.