XP still has a massive lead over both Vista and Windows 7. Businesses and consumers despised and rejected Vista from day one, and Microsoft acknowledged that failure. But it did ship on new computers for quite some time, so takes the distant second place.
One would have to assume that people are only moving into Win7 with the purchase of a new computer, rather than buying it to install on a current computer. And computer purchases must be slim, since Win7 has been shipping on new computers since around Christmas 2009. I was shocked at such a low percentage of Win7 users, as it has gotten fairly good reviews from techies. Although when you look at it another way, there are more Win7 users than Mac users, and Mac OSx has been around for a heck of a lot longer than 9 months. So Win7 certainly has market share.
The other/unknown browser category include some iPhones, Win2003, WinNT, network servers, and search engine crawlers. None of them accounted for more than a few percent each.
