In its first month of sales to the general public, Windows Vista sales broke 20 million, making it the fastest selling version of Windows thus far. Obviously, Microsoft is going to spin these numbers for all they're worth, but it's really only natural that a years-delayed OS released to an increasingly PC-ified world would sell like gangbusters. With 239 million PCs sold globally in 2006, 20 million doesn't sound like a terribly impressive number, but at least it's nothing to sneeze at. The number includes OEM sales, retail sales, upgrades and Vista Express Upgrades between January 30 and February 28. In comparison, Windows XP sold 17 million copies in its first two months on the market. Other fancy numbers Microsoft is bragging about include 4,500 "Certified for Windows Vista" products and 27,000 drivers, with a respectable portion of those appearing after Vista's launch. No word on how positive Vista's impact has been on general PC sales, and we're confused as to why people like Steve Ballmer would be blaming pirates for "poor" Vista sales when Microsoft sounds so excited about this 20 million number here, but we're guessing the good news from the PR side of Microsoft isn't going to do anything to slow a WGA crackdown.