SSS is a marketing term thrown around by Yamaha, from 06 onwards as per previous post. 05 had an twin chamber design that wasn't the best.
AOS is still the same/similar design now used on Kawi/Honda/and GG
Like everything, there are some changes between models. Different spring guides, different mid valve piston setups, different clamping OD's at the upper fork, a couple different lengths, various lug offsets too. Quite a few threads if you have a quick search that cover geometry.