Microsoft has sold 175 million Windows 7 licences in 12 months

"Software giant Microsoft has posted a big rise in quarterly profits amid signs of a rebound in technology spending by corporate customers.
Revenues hit 16 billion US dollars (£10.5 billion) in the second quarter, an increase of 22%, as profits jumped 48% to 4.5 billion dollars (£3 billion)
The results, which were stronger than Wall Street had expected, were helped by strong sales of Office 2010 as revenues from the company's business software segment rose 15% to 5.3 billion US dollars (£3.5 billion).
Microsoft added that more than 175 million Windows 7 licences had been sold since its launch last year."
Source:  Official Microsoft results, reported by the Press Association, 23rd July 2010
Note - Windows 7 launched to the trade on 22nd July 2009, and to retail on 22nd October 2009