Written by students and others associated with Duke's PhD in New Testament.
I've used zotero thus far and have really enjoyed it. It's a firefox plugin that can automatically grab bibliographic information off of webpages (amazon, libraries, etc) and store it. It also has a ms word plugin so you can add footnotes/references/bibliographies directly from zotero. They have beta support for SBL currently: http://www.zotero.org/stylesI'm sure it's not perfect, but I've definitely loved using it so far.
Citation has worked relatively well. Last time I used it they had an 'experimental' version of the SBL Style. www.citationonline.net From what I can tell, there is no 'perfect' bibliographic/footnote program. The various styles out there have a lot of tiny rules that just don't work well when it comes to a computer making the decisions for you.
Nathan - There is an SBL-style filter for Endnote. It's not perfect, but works OK. I'm using it for my dissertation. If you don't have it, let me know and I'll send it to you.Ben
I have migrated over to Endnote X5, and I also downloaded their style output for SBL. However it really does not do a good job of formatting citations correctly. Before I try to learn how to edit that file, I have to find out if anybody has already done that to create a good SBL output file like Citation 9.1 used to have.