I've been using the latest build of Mozilla on OS X for about a week now. So far it hasn't been bad. There's some obvious bugs, but none that are showstoppers and nothing that causes it to crash any more frequently then IE did.

Mozilla has some sweet features:

Ability to block images by server (no ADS!)
Ditto on blocking/allowing cookies
More control over what sort of javascript you'll allow
Control over popups
tabbed windows (not used to them yet)

IE and Opera each have some of these or similar features, but none of them quite as extensive. Rendering isn't bad, at least on my G4, and navigation is easy.

For anyone who cares (browser programmers I would hope) here's what I look for in a browser:

easy to view page source and image properties (at least W & H)
bookmarks & folders in top nav bar
able to shrink menu bars
can drag a link from one window to another OR to bookmark navbar
control over caching...that works reliably
bonus points for good cookie, image, javascript control
consistent page layout, supports modern standards
not too much crashing, but this isn't highest priority

Mozilla goes a long ways towards this and so far I haven't felt like going back to IE. I've tried Omniweb (nice looking, but beauty is only goes so deep), Opera (bad handling of links/dragdrop), and IE. Before Mozilla IE was the best for what I do and how I work, but it always has at least two or three really annoying bugs (Win or Mac) that interrupt the flow of work. I tried Netscape on Windows a month or so ago and after picking all of the AOL detritus off of my hard drive I'm happy to say I won't ever make that mistake again. IE may be annoying but AOL/Netscape takes annoying to a whole new level.

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