Sounds really left field considering all the nonsense in the first season.
To be fair this could have been a really interesting thing, but in reading about it and what I remember of the first season... It sounds an awful lot like the writers just never knew what to do with her, thought it was cool to have Korra have a friend who happened to be a girl and then somebody made the girlfriend joke and... bam.
Having her, or Korra, being lesbian isn't my problem. It's just that if they wanted to go that way they should have been doing that from day one, and it should have been an important part of the story all the way through. It seems like a giant missed opportunity for some great build up and story telling.
Which seems to be the reoccurring problem with the series. If they had built up the story, the main characters, their relationships and their villains I think this show could have been amazing.
Imagine an Amon as reoccurring nightmare fuel over four seasons... and well, hopefully a better reveal. Maybe as being that darkness spirit thingy trying to remove bending from the world.
Of course I was kind of rooting for Bolin and "Mrs. Jabroniville" hooking up, so I'm a dirty filthy shipper who should be burned and otherwise ignored ;~)