HootSuite has 5 million users

"On October 12, 2012, HootSuite reached 5 million users.
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What does five million look like? At five million users, we span the globe. Our expansion into Europe, Asia and Latin America is driving our growth, and there’s a good chance we speak your language. How fast are we growing? The first million took nearly two years, and the fifth million took just five months.
We are proudest of our international growth and global reach, which has been sparked by listening to users on the ground and responding to their requests. In doing so, HootSuite Community has hosted over a 100 HootUps, assigned regional Diplomats, translated our tools into 20 languages and offered regional apps. Our tools are in use on screens in such diverse locales as Irkutsk in Siberia, San Francisco advertising agencies, London multinational brands, Egypt during their revolution and over on the tiny islands of Palau."

Source:  Blog post by HootSuite, 1st November 2012