From the press release:
More than 2.6 million people used Opera Mini on their iPhones, in the two weeks following April's mid-month launch. This surge in new Opera Mini users reshaped both the top 10 countries and the top handsets for mobile Web usage, according to Opera's State of the Mobile Web Report, issued today. The United States jumped two spots in the top 10 country ranking, displacing South Africa and Nigeria. Globally, the iPhone immediately became the third-most-popular device for Opera Mini users worldwide.
TBH, I don't find that bit about the 2.6m users to be all that interesting. The really interesting part of this announcement is that Opera tracks users of their browsers. I'm more than a little creeped out by the level of detail in the monthly reports. I'm going to go uninstall Opera and double check that TOR is running properly.