It seems that just at the moment that brilliant has passed the ironic tipping point in the U.K., American commerce has decided the time is right to adopt it. Brilliant.
It seems that just at the moment that brilliant has passed the ironic tipping point in the U.K., American commerce has decided the time is right to adopt it. Brilliant.
notoneoffbritishisms.com 
I don’t know. The advert seems to be using brilliant in its more narrow meaning – ingenious or very clever or the result of a moment of enlightenment. It has long been common in Britain and to use brilliant just to mean very good. “Tea? Brilliant.” I only realised some time in my teens (the 80s) that brilliant had a more specific meaning.
To appreciate the depths to which this can be taken, I can only refer you to the brilliant Paul Whitehouse in the brilliant Fast Show:
To my British ear there’s something a bit wrong with both those ads.