Mozilla Messaging (opens in new tab)

I don't know about that. I think there are a lot of people that would, all other factors being equal, prefer a desktop application to a web application.

I'm one of them. Maybe I just haven't drunk enough of the Web 2.0 Kool-Aid, but I think people (especially around here) are too eager to announce the death of desktop applications.

What choice do they have? Mozilla's strength is in desktop GUIs, so it would be risky to start working on server-side Web 2.0 mail. If Web mail is indeed the only future of mail, then I guess Mozilla should just shut down their mail efforts.