The Google Browser Sync Firefox extension project appears to be coming to a close, according to Google Operating System. The team behind management was very small, apparently, and the tool won't be seen in Firefox 3 (which is expected to launch officially tomorrow). The extension, by the way, allowed you to sync all of your bookmarks, web history, and passwords across multiple browsers.
Unfortunately that means that some people who have relied on the efficiency of the tool are out of luck. I'm not sure if there are any suggested Firefox replacements that would work instead, but if you know of any, please add them to the comments.
Forum discussion continues at Search Engine Watch Forums.
