Link Layer Topology Discovery (LLTD) Responder (KB922120)

This package contains the Link Layer Topology Discovery (LLTD) responder. The network map on a computer running Windows Vista shows a graphical view of the computers and devices on your network and how they are connected by using the LLTD protocol. The LLTD responder must be installed on a computer running Windows XP before it can be detected and appear on the network map. After you install this item, you may have to restart your computer.

Also: Internet Options/Connections/LAN Settings: check box automatically detect settings

Then, once you see the LAN in the Network and Sharing Center, click on View Status/properties/Sharing (I checked these 2 boxes, not sure if this made a difference or not)

Finally on syncing files: I was able to map to an XP folder from Vista and make it available offline (so the original still lives on Vista), but not the other way around. So I have my key folder living on my XP machine and the Vista machine and the Tablet both sync to it.