Welcome to the Weave group!
Weave is a Mozilla Labs project to explore ways in which the browser
can broker richer experiences on the Web, by integrating more closely
with online services.
The first component of the Weave project to be available
for testing is Weave Sync. It is an add-on and a server which allows you to
synchronize browser-related personal information (such as bookmarks,
history, saved passwords, open tabs) to a server and all your devices.
You can use
Mozilla's server, or you can set up your own as well (see
here for instructions).
If you have any questions, first check the
Weave FAQ, as many questions are already answered there.