Hello, Paul.
Live Mesh is a beta and the details of what it can do are documented at
www.mesh.com After you've reviewed what is there, you can give it a try, but I will suggest that any files you plan to include in a Mesh folder to sync between PCs should not be your only copies of those files - have a good backup in a different location.
If you have specific questions after reviewing the documentation, come on back and post them. To try and give you an overview here would be unwieldy. :-)
-steve
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