Back in December, Eric Lee posted his Team Foundation Server Work Item Utility in GotDotNet CodeGallery, which he built for moving work items between team projects. You can find more information about it on CodeGallery and in his blog post, Instructions - Moving work items between Team Projects.
This is an early release of WITUtil; it will do the following for one or more work items that you choose: - Identify if the destination Team Project has a matching WIT; optionally imports the WIT from the source Team Project - Adds a 'Moved' state to the WIT in the source Team Project and sets the moved work item to this state - Re-creates most fields in the destination work item, including attachments and links. Some fields are computed and cannot be re-created.
Team Foundation Server Work Item Utility: Home.