It's the little things that make a difference. A tiny little bug in safari has pushed me over to using Firefox as my main browser on Sedna. On the invitee-editor of the invitotron, there's a list of the invitees in the database. With a dropdown to filter them by groups. If I select certain groups, the image buttons next to the drop down don't render when the page loads. Other groups they do. Rename the <select> tag, it still happens. Remove the <select> tag, it works normally (except, of course, I can't change the filter). So, hell with it. Browser bug, switch to firefox.
Firefox on mac lacks some features that safari has that I really like. Command-down takes you to the end of the page. This is important, as the end key if Function-right, and requires two hands. cmd-down is a single-handed command. Things like that. Also, if several tabs have a common prefix in the <title>, safari will strip it. So, say a tab "Amazon.com: foo" and "Amazon.com: bar", the tab titles would be "foo" and "bar", which is nice, 'cause you can see the meaningful part of the title, instead of "Amazon.co...". Things like that.