By now everybody knows that Firefox 0.9 (8Mb freeware) is available. I use Safari and Firefox all the time. I tend to use Firefox for checking on the spam trapped by my server and for certain other specific websites such as banking.
Also invaluable to me is the PNH Developer Toolbar which includes these features
- Links to most W3C Specifications
- Automated submission to many validation tools
- Hide & show style sheets
- Apply your own external style sheet
- Highlight many HTML elements
- Resize Window to specific dimensions for testing
- Highlight form information
- View page cookies
Also useful and interesting are the Tabbrowser Extensions for extending operations of tabbed browsing, eg tabs become re-ordable by drag and drop, change the colour of tabs, duplicate tabs and so on. I haven’t used this one for more than a couple of days, but I like it.