According to Alfred Gough and CBR:
Green Arrow is going to be back around Ep 11 and they are going to introduce a new JLA character that we haven't met before in Jan.
Kara is in 12 of 22 episodes. Lois is in 12 out of 22. ...And Lana has just got back into town. Her story is going to get more interesting and a little darker. What you are going to see after episode 8, Kara gets benched for a couple of episodes, and you will see why, I won't spoil anything
you haven't seen the last of Bizarro. It's kind of the season of reversals. Clark was the child and is now the mentor. Chloe was the freak hunter and now she is a meteor freak. Lana, who was always complaining the Clark kept secrets from her, is now keeping secrets from him. I think, like I said, are a lot of relationship reversals this year. That kind of drives the bigger story lines. And Kara and Krypton and all that stuff, plays a bigger role as we delve into that a little more, as well.
Some other misc spoilers that I can't remember where I read them - giving credit to Kristin at E!, Ausiello at TVGuide and the above CBR but I can't place specific spoilers to specific sources. Feel free to treat these as rumor and speculation otherwise.
- Helen Slater is playing Lara, Clark's mother, She will be in more than one episode.
- Jimmy & Kara hook up
- Chloe is still Watchtower and still working for Oliver.
- Clark gets a red cape as a gift.
- Martian Manhunter will be back
- James Marsters will be back
- The new Daily Planet editor has ties to Lex and isnt what he seems
- Bizarro will be back