This morning I watched a brief screencast on FF3, with a focus on Advanced bookmarking and tagging.
It's a terrific screencast.
The FF 3 bookmark and security features are even better than I'd realized -- and I've been running FF3 on my macs for weeks.
This is one heck of a browser launch. We're spoiled on the OS X platform now, with both Firefox 3 (blessed by Google) and Safari 3 (blessed by Apple) as excellent choices. The primary drawbacks of FF 3 for OS X are the lack of Cocoa integration (no services, no dictionary lookups) and the lack of AppleScript support (even less, currently, than FF 2). (I use Camino on my aging 10.3.9 iBook and I very much love its Cocoa integration. I'd really like to see a future version of FF 3 and Camino merging, perhaps adapting the tab management features of OmniWeb.)
Firefox 3 beats Safari by a country mile though when it comes to bookmark management. No more of that silly filing and organizing -- unless you REALLY want to do it.
One click to add any site to the unsorted collection. A second click (or a double click) to change the default name and add tagging. Tag model is similar to bloggers, easy to type or select from an on-the-fly dictionary (flat ontology). It's easy to see how well with will work with bookmark synchronzation and integration with web bookmark services. The search model is seamlessly integrated into the url field.
This is the way I've been managing my Outlook email for about two years now -- tagging, renaming subject lines, minimal filing for special projects, full text search.
Update 6/8: More great FF 3 features.