There has been a good deal of talk surrounding Rachel Elior's hypothesis that Josephus invented the Essenes from whole cloth (later qualified,etc.) No-one in the English side of the blogosphere has yet cited Meir Bar Ilan's devastating review on Elior's earlier foray into Qumran studies - here.
While we will not be able to really judge Elior's hypothesis until it is actually presented to us in its book form, I'd like to make a couple of comments. First, that Josephus's portrayal of Essenes (and Pharisees, and Sadducees) is somewhat problematic is well known. As you can see here, Josephus did attempt to have the various Jewish sects correspond to Greek philosophies for apologetic reasons and he was not above manipulating some of the details to suit his purposes.
Most of Eliors arguments , in her note here seem to arguments from absence. The lack of references to Essenes in Rabbinic literature or the NT is of no more significance then the lack of references to the "Na-Nach's" on this blog.
R Reuvein Margoliyot did try to find an indirect reference to the Essenes in the Talmud, I think he is wrong but its worth repeating anyway. On the statement (end of tractate Kiddushin) טוב שברופאים לגיהנים - Margoliyot suggests rather cryptically that one who understands the history of the beginning of the group of Essenes will understand. I think he is making some type of connection between the word אסיא - healer and Essenes but I don't think it works.