[Updated 9/26/14] Rather than make another new posts since this was just published, I’ll edit/update this one. I’m now reading comments (confirmed?) that there will be FORTY (40) ship girls in the anime. Also, there will be some theme episodes such as one focusing on the Kongou (class) sisters, an episode on Yamato (of course), and one on IJN Destroyer Division 6 (all four Akatsuki class DDs) which is most likely a reference to a quest in the game.
As of this update, Atago (CA), Zuikaku (CV), Kitakami (CL/CLT?), and Ooi (CL/CLT?) are confirmed raising the current total number of ship girls in the anime 21, leaving 19(!?) more to go if that 40 total comment is correct. I’m still guessing that if Zuikaku’s in, Shokaku (CV) is also in, and if Atago is in, then Takao (CA) will be in as well. I’m also anticipating at least a couple of CVL (hoping Jun’you is one of them) and subs in the anime. Lastly, progress on the adaptation is said to be going well. The script is finished, and a second PV is scheduled to be released in the next month or two.
FYI – Atago official anime image added to the KanColle Primer. Have to say, anime Atago looks quite good – better than her game character image in my opinion. I will add official images for the others when available.