And you thought it was mostly Americans addicted to the SMS/IM/web presence thingamy… ? Web measurer Hitwise says it’s the reverse - at least, proportionally. “Last week the site’s share of UK internet visits was 70 percent higher its share of visits in America,” said analyst Robin Goad. ”Twitter cannot yet be considered mainstream in the USA, but in the UK it’s getting there.” Its growth here - 485 percent so far this year and 631 percent year-on-year - is slower than the eightfold annual international increase, though.

Twitter may seem too esoteric and the crowd too geeky to be adopted by the Facebook masses, but Goad says the “demographics are also pointing towards more wide-spread adoption”. Last month, the audience was evenly split on gender and over-45s made up 37 percent of users. And, while the most prevalent users are high-rolling “city adventures”, students and young professionals, young families, ethnic-minority singles and “white van culture” (for our American readers, “a white van man” is sort of equivalent to a pick-up driving worker) are also heavily represented, suggesting “more mainstream appeal”, Goad said. Fancy metrics aside, the barometer I always use is the girlfriend test - if she’s adopted a new technology (hey, it happened with Facebook and Last.fm), you know it’s reached a tipping point; she started tweeting several weeks ago. Now if only Ev and Biz would tell us their business model..

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