Okay, I finally got around to watching these episodes. I didn't even know they were premiering last week until my brother told me...very abrupt premiere I feel like. I think this is why it only got about 1.5 million viewers according to Wikipedia, which is about half of the other seasons. But anyway, the show is great so far, I think this season is way better than season 2. The new characters are great and the pacing is much better. The bridge scene in the first episode was one of my favorites. They (of course) didn't outright say it, but it was very reminiscent of those interrupted jumper suicide scenes from other shows and movies.
I also really like the way they handled Team Avatar trying to recruit Airbenders. It's not exactly easy to get someone to change their entire way of life just because someone they don't even know told them to, as most religious missionaries know. I'm glad the show realized that too and also touched on whether or not these new benders actually really had any obligation to rebuild the almost extinct Airbending culture.
As for the characters, Korra still has a hot temper but for the most part seems like she has finally matured, rather than being reset like last season. The Mako/Korra scenes are super awkward and painful to watch but at least they're broken up (hopefully for good). However, the Mako and Bolin scenes are great. Bolin is the best character, he is hilarious and I strive to be like him in every aspect of my daily life. Kai is interesting, as are the theories about if he is related to Sokka or The Duke or something. Personally, I'm just glad that little shithead got what he deserved by the Dai Li (Yea I'm rooting for the bad guys).
I'm hoping the Earth Queen and the Dai Li turn out to be true villains, that is, stay villains even when the new super-benders arrive. It'll be interesting for them to go against each other as well as Team Avatar.
P.S. this is totally unrelated but I really want a Legend of Korra and Godzilla crossover