Toaru Hikuushi e no Koiuta is the highlight series in the romance department so far in the Winter 2013 season, in my opinion. Even though Nisekoi is very good, but the development in this series is very good right now.
At first it gives you a feeling of just another series about a normal guy who trains to become one of the best and try to get a girl, while some jerk elite guy is trying to sabotage him and steal the girl away.
BUT that's not how it turns out to be at all, the series starts to really get going in the third episode when they start showing the main character's past and motives, then boom you are hit by the end of the fourth episode. So far this series is showing a lot of promise , so I'm hoping it won't screw up along the way for the rest of the season.
Btw, I found these interesting;
http://www.crunchyroll.com/anime-new...-anime-of-2013
http://www.crunchyroll.com/anime-new...-tweet-ranking