Mozilla Firebird 0.6 (formerly Phoenix)

The long due Mozilla Firebird 0.6 release is out

Mozilla Firebird 0.6 (formerly Phoenix) is available for download. This release features a fresh new look, a redesigned preferences window, preliminary support for Mac OS X and much more. Read why you should be using Mozilla Firebird and get the latest release.

[Slashdot]

You should definitely give it a try. The tabbed browsing and the extensions are just wonderful.
Still lacking the "Send a Link" and "Send Page" commands though :-(