There's still a market for people who want to manually upgrade. There was a comment thread on HN a few months ago about this as well (no way we'll be able to find it now, I don't remember the story), but it summarized my views very well. I like knowing what is or isn't being installed on my computer. I've got a bash script to automatically download and update to the newest Firefox, so the act of upgrading isn't a chore. But I don't want a given company, be it Google or Mozilla, to arbitrarily change what's on my computer.

That's not to say I don't see the allure of automatic updates, but I just don't want them to be silent and mandatory.