This morning's Passages on the Mariner listed changes to the SSS tier levels for 2007. New enhancements are, in addition to existing benefits:

Silver - Invitations to exclusive Regent cruise and hotel events in select cities.

Gold - Choice of newspaper services from around the world.
Complimentary upgrade to hardcover of personalized commerative album at soft cover prices.

Platinum - Complimentary Air deviation services (once per sailing.)
Additional 6 hours of complimentary phone usage per suite (non-transferable or exchangeable.)

Titanium - new level for 400+ nights -Complimentary transfers to and from airport and home (within a 50 mile radius.)
Complimentary dry cleaning.