The New York Times has a story about the explosive growth of Firefox, and how Redmond’s screwed, at least in the short term. There may be only one way out, as Scott Ott amusingly points out.
But another article says that Thunderbird, its email client companion, won’t be able to make as many inroads against Outlook, no matter how insecurity-ridden that program is, because of the energy barrier necessary to change email clients.
Email and Usenet are the biggest things keeping me from switching to Linux for my desktop–I just have too much legacy data in Eudora and Agent, and no obvious way to transition over to things like Thunderbird and Pan. I use Mozilla for browsing, but I’m still using Eudora and Agent, until there’s an open-source solution for this problem.