The Center for History and New Media at George Mason University has released the Zotero 1.5 Sync Preview.
Here's an excerpt from the announcement that describes its features:
- Automatic synchronization of collections among multiple computers. . . .
- Free automatic backup of your library data on Zotero’s servers.
- Support for thousands of existing Endnote® export styles. . . .
- A new style manager allowing you to add and delete CSLs and legacy style formats.
- Preliminary support for local sharing of collections through ZeroConf on OS X. Other platforms and full support to come with the final release of Zotero 1.5.
See the documentation for additional details.