Microsoft seems pretty confident it can sell a lot of Surfaces. Supply chain sources have told the Wall Street Journal that Microsoft has placed orders for between 3 million to 5 million Surface tablets for the fourth quarter of 2012, which the Journal notes is around what Amazon and Google have ordered for their flagship tablets in Q4. The Journal’s sources also said that mass production for the Surface started ramping up earlier this month. Microsoft will officially launch the Surface at midnight on October 26th. Read the full story at Boy Genius Report.