Originally known as Foxmarks, Xmarks takes the original, bookmark-synchronizing concept behind the plug-in and mashes it with a style of Web site discovery reminiscent that should feel familiar to users of StumbleUpon or Del.icio.us.
Xmarks maintains its utility in this major update, retaining focus on synchronizing your bookmarks so you can access them from any computer running Firefox. A simple start-up wizard guides you through the set up, after which it indexes your bookmarks. After installing Xmarks on a second computer, it gives a choice to merge or junk bookmarks from either rig. New to this version are an expanded set of Options for configuring how and when the add-on will synchronize, synchronizing passwords as well as bookmarks, and creating profiles to better manage disparate sets of bookmarks. Other tweaks include hosting your bookmarks and passwords on your own Web site instead of Xmarks', rudimentary encryption management, and determining syncing up or down.
The big news about the update to Xmarks are the site discovery features. It now installs an icon on the right of the URI bar, which you can click to reveal more info about the site you're on and other similar sites in your browsing history. It will also highlight the your Google results based on how many other Xmarks users have bookmarked them. While this may seem scattershot, Xmarks claims their users have marked more than 600 million Web sites--that's a lot of data to mine. If you don't trust Xmarks' data encryption, you can opt to not sync passwords, but there's little doubt that this is a bold attempt to bring Xmarks--finally--into Web 2.0.