Well, i did call it, i said leaving the show would be a huge mistake for her, i doubt if she will get any mainstream work after this. Happens to most actors in hit tv shows...
Jorja Fox said in her interviews she wasn't interested in doing any prime time tv for a while, and would only do guest spots on CSI. She is taking a break and devoting her time to her many humanitarian causes and her personal life. At this point in her life maybe she doesn't want mainstream work; she seems to enjoy doing indie films and was excited about the play she produced. I don't expect her return to be full time to CSI, but I will be happy to see her back on the show even if in limited capacity.
I agree that Sara will remain a background character but hopefully she will stay in LV and be part of Grissom's life. If they break them up again that would be way too OOC. I am interested to see what her character will be like when she returns and what her job will be; maybe she will go back to school and finish her doctorate in physics. I doubt we will find out anything about this in the first episode; this will be all about Warrick and the fallout from his ordeal. I also believe now that he will survive, somehow.
I wonder if they will still make Wendy a CSI. The new female is now going to be a CSI instead of a detective, and we haven't heard anything about a replacement for Wendy in the lab, so maybe they are holding off on this storyline for now.