CritterNYC - 2:14 am on Sep 30, 2011 (gmt 0)
StatCounter has never been a good representation of the overall web and is only used on a few low-usage web pages these days. It's basically representative of nothing except some personal web pages in specific countries.
NetMarketShare shows Firefox at 22.57% worldwide and Chrome at 15.51% and is a far better representation of the overall market.
It does vary by geographic region as well. Firefox is higher in Europe and I think is the #1 browser in Germany at the moment.