But oddly, many of the world leaders who joined Twitter "don't bother to follow each other," the Associated Press pointed out.
About 60 percent of world leaders now have a Twitter account, according to Burson-Marsteller's "Twiplomacy" study.
The firm monitored 264 Twitter accounts used by governments in 125 countries, and Obama came in first. (Second? What up, Hugo Chavez over at @chavezcandanga.)
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Obama scored fifth in the whole Twitterverse, putting him closer to @britneyspears than he is likely ever to be in real life.
He comes in one behind the pop singer in terms of global Twitter popularity, but he's way ahead of her -- and everyone -- with the actual tweeting. Yes: Obama's May 9 "same-sex couples should be able to get married" tweet is the most re-tweeted tweet ever, the study found.
But the US leader rarely replies and only eight of his 5,000-odd tweets were actually signed with his initials (meaning: he actually typed them), reported Reuters, going on to suggest that Twitter fans follow more interactive leaders like Uganda's @AmamaMbabazi or Rwanda's @PaulKagame.
Of course, interactivity can come with a cost. Tweets are becoming ever more of a public liability these days -- they're even capable of ousting Olympians! -- so it's worth noting that of the three obsenities tweeted by world leaders, only one hasn't been removed.
The tweet by Estonian President Toomas came in response to economist Paul Krugman, said Reuters: "Let's sh*t on East Europeans: their English is bad, won't respond & actually do what they've agreed to & reelect govts that are responsible."
Er. Not exactly Twiplomacy.