The above graph from Wikipedia shows the top six methods for browsing the internet: IE, Firefox, Chrome, Safari, Opera and Mobile Web. Roughly looking at these graphs we can see that there is a steady pattern: Internet Explorer is losing users, Firefox and Opera are staying steady, and Safari, Chrome and Mobile Web are gaining users, Chrome is gaining rapidly. By mid-2011 I see it as fairly likely that Internet Explorer usage will have probably dropped below 40%, and by mid-2012 Google Chrome will have over-taken both Firefox and Internet Explorer. If you’d asked me six months ago I would probably have said that by the end of 2011 IE will still be the most used, but Chrome will have more users than Firefox.
It is hardly a surprise that Internet Explorer is rapidly losing users, it is struggling to stay ahead and despite that desperate TV marketing campaigns, it is clear that Internet Explorer is on the demise, with Google sticking a Chrome ad on pretty much every Google owned site, including Google ads. Firefox is also now the most used browser in Europe, but I think one day Firefox will also die a death.
As for Safari getting more users, that can only be down to more Mac sales.