Although comScore only measures visits to Twitter.com, and more than half of Twitter users use clients and apps, it does provide a clue to Twitter’s growth rates.
In June it gained around 7 million new visitors, hitting 44.5 million unique global visitors, up 19 per cent from May 2009, and now making it the 52nd biggest site in the world (and with a 55 per cent international audience).
Techcrunch points to the Iran election as a contributor to the growth, while Mark Evans over at Twitterati somewhat confusingly uses comScore and Compete figures to calculate a 50-50 U.S and International split.
For the record, the biggest properties measured by comScore are Google sites, Microsoft sites, Yahoo sites, Facebook and Wikimedia Foundation sites.