I note that Janco put out a press release in September that has a gorgeous graph showing IE’s market share for a full decade, from Sept. 1997 to Sept. 2007. While I consider their Netscape numbers in the press release to be (seriously!) wrong (and specific numbers do vary (sometimes considerably!) between research companies), the trend is clear: IE increased rapidly from 1997 to 2001 (Browser War I), plateaued in 2002 (inter-war period) and then began its current decline in 2003 (Browser War II). I’ve taken their graph and added indicators of when major versions of IE and FF were released:
As you can see, Microsoft actually did a good job of releasing a new version every year to year-and-a-half from IE4-6. They sowed the seeds of their own destruction by not releasing around 2003 though; in order to just keep up with the web they would need to maintain that 12-18 month release schedule. “Release Early, Release Often” is a good strategy. Of course, by then the IE team had been disbanded in a short-sighted move; “We need those great people on products that make money!“. As you can see though, Firefox has done a good job of maintaining a release schedule of ~12 months (FF3 should be out soon; its running a bit late though) and their market share has been increasing nicely.