The key feature in Mozilla's Weave add-on for Firefox is the ability to synchronize tabs, bookmarks, history, and other browser-sourced, data-rich fields. The latest update, Weave version 0.7, gives a big overhaul to the synchronization component, redoing the setup and configuration interface, and adding incremental download support.
Compared to previous versions, the installation process on your first computer has been greatly streamlined, though the security questions asked remain the same. The wizard that guides you through the process has been redone to present the information through a tab-specific black overlay.
According to Mozilla, the incremental download support will grab your data in bite-size chunks to spread out, and reduce memory and network usage. To redo the synchronization settings, you still need to load the Preferences via about:weave, and then go to the Tools drop-down menu on the tab that opens and choose Start Over. I was unable to synchronize many settings, but that might be because of a conflict with an installed add-on.
The development of Weave, first introduced at the end of 2007, didn't really begin to take off until earlier this year. Since then, Weave has introduced multiple useful features that other browsers, such as Opera, have had for a while. Weave can also sync data between Firefox and Mozilla's mobile browser, Fennec.