Oreimo and Haikyuu!! were definitely the biggest surprises for me.
When I first read the description of Oreimo, I thought it was gonna get really fanservicey and pandery. But I watched it anyway, since the idea of a little sister being really into eroge seemed kinda interesting.
The first half of Oreimo, Kirino really pissed me off, but I couldn't stop watching the anime and I actually absolutely loved it! It was fun, cute, and pretty entertaining. Kirino's tsundere BS was pretty annoying at the beginning, but it really grows on you. And then you realize that maybe she's kinda cute.
But then season 2 of Oreimo came out, and it was mostly harem, incest, bs... So that kind of sucked.
BUT OMIGOSH. I NEVER WOULD HAVE EXPECTED HAIKYUU TO TAKE OVER MY LIFE LIKE IT HAS. It's definitely my favorite anime right now.
I'm not really into sports anime (except for Free), and volleyball is one of my least favorite sports. But after seeing a lot of people talk about it on Tumblr, I thought I would give it a try. AND OMIOGSH IM SO HAPPY I DID. It's just such a fun, inspiring, funny, and PERFECT anime. I adore it.