Nothing much has changed since the Tahiti release though the latest version looks stable and sports a more polished interface.
With SharedView, a maximum of 15 users can hold a live meeting, share screen and collaborate real time. You will still have to wait for future ShareView releases to get audio support or chat function.
Only the host or the person who initiates a SharedView meeting requires a Windows Live ID, the participants or invitees to the session can join without signing up as long as they have the invitation password from the host.
Microsoft has added a strange clause that says "This Service may only be used within the United States of America." though it is technically possible to use the service anywhere since they are not checking the IP address of the host or guest computers yet.
Download Microsoft SharedView [~3 MB] | Help docs | Thanks Mary