A fellow Gavin writes in the Register that:
Janco Associates found IE had 83.7 per cent of the market for this month, down from 84.85 per cent, while Firefox grew from 4.23 per cent to 10.28 per cent. Janco believes Firefox could take 25 per cent market share in the next quarter.
Separately, Infocraft reported the browser is approaching nearly 50m downloads, up from February’s milestone figure of 25m, which was recorded 99 days after Firefox 1.0 became available last November.
That is rather quick growth indeed.