Finished this up (started on Crunchyroll but then just downloaded the torrent) and its pretty good.
Shirobako is about (wait for it) a group of high school girls who (wait for it) started an anime club in high school for (wait for it) the school festival. hahaha
After that the anime does enter into uncommon ground... the series mostly follows Miyamori Aoi as she gets her dream job as an production assistant at Musashino Animation a lower end anime studio with B-list talent. You get to meet a LOT of characters and see a LOT of Japanese work culture (well, most a satirized version.... I hope it is... although from reading forums it seems that its more or less accurate) and see how powerful businesses shit on lower tier ones. I have no idea if this is truly how animation studios work (tight deadlines, lack of personnel, late, late hours and lots of OT) but the story does show many, many different aspects or work life. It seems that anime is still more of a cottage industry for the lower end studios.... but then again, I don't really know.
The story progresses as Miyamori learns the ropes and advances through her career. Best I can tell the series covers at least 2-3 years and covers the making of two anime series.
The story is really about Miyamori and her friends realizing the dreams they had to get into the anime business... each had their own 'specialty' (animator, voice, producing, assistant) and they all work towards, then finally achieve their goals... so when all is said and done its actually a 'happy' ending and everyone moves forward.... and its always rare to watch an anime have a decent wrap up for the characters.
Its 20-something episodes.... and really worth a watch if nothing more than to see what Japanese think of their business culture.