For those who have the global version of the SGS II, this has just been put up on Engadget:
http://www.engadget.com/2012/03/08/samsung-galaxy-s-ii-ics/
Edit: And here's an FAQ/Advisory from Samsung:
http://skp.samsungcsportal.com/integrated/popup/FaqDetailPopup.jsp?seq=422548&cdsite=ph
Upgrade may be via Kies or OTA.