I probably don't have all the facts but I'll give this a shot anyway.
The difference aside from the cosmetic (different finish options, different Ambience Tweeter Knob) are in a slightly modified midrange driver. The modification started a chain of events. Albert being Albert meaning a certified perfectionist, he re-did the crossover for it to better match the driver. Comparing the two of them, the anniversary is a bit more palpable with a more "you are there" feeling. The differences are definitely there but not that major as was the case from SR Mk.1 to SR Mk.2. As such, the retail price stayed the same but the piano gloss finish which was a very expensive option in the past is now standard. The upgrade of the innards is straight forward and is field upgradeable by authorized dealers. Meaning one need not send the loudspeakers back to VS HQ in California.
I will miss the Ebony finish most. Especially the very rare Tiger Ebony 4SR and 5 SE units that are bound to become collectors items. AFAIK only 6 Tigers ever came out of the Factory. One of these SRs is here. I swear, when I saw it when delivering the pair at the clients house I almost withdrew the sale.
Albert also did away with the Data-Link cable. Being a SOTA loudspeaker, nobody who'd buy it would use the DL anyway. It makes for a much cleaner rear end and enhances the elegance.