I'm almost a member of the 50+ crowd. Git yerself a copy of FireFox and lend a hand. 1.5 seems pretty zippy.
In order to really get over the hump, though, I think Mozilla.com needs to bring back some of the distribution features that the old Netscape browser had. Specifically, we need the ability to control the rights to change features in the browser. Push distribution across the network would be good, too. And don't forget corporate branding – oh wait, you can already do that with a skin.
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