Following last night's premature access to iTunes Match some users in international markets were able to achieve through their iTunes Store account pages, the service now appears to officially be going live in several countries.
iTunes Match link on front page of UK iTunes Store
Users in those countries are reporting successful sign-ups for the service, and we're waiting to hear confirmation on whether it is indeed fully functional at this time.
Update: We're also receiving reports of iTunes Match links going live on iTunes Stores in Australia, France, New Zealand, and Spain.
Update 2: Users are reporting that the iTunes Match does appear to be working in the new countries, with subscribers' libraries being matched.
Canadian user's library being matched
Article Link: iTunes Match Goes Live Internationally (For Real This Time)