This was back when Internet Explorer was at version 7. Some Mozilla folks told me they used to get questions like "when are you going to upgrade to Internet 7 like Microsoft?"
If I remember right, after Firefox 4 they skipped a few versions and started the train model, while also trying to de-emphasize the version number in marketing.
If I remember right, after Firefox 4 they skipped a few versions and started the train model, while also trying to de-emphasize the version number in marketing.