Apple-Shift-left and Apple-Shift-right to switch tabs.
You might want to give Camino a try. I've spent about 1/2 day last weekend trying to decide which browser to use on my Mac, and I chose Camino.
Here are some of the things that I've found.
Camino
+ Better integrated look and feel.
+ Better cache management, so pages come up faster.
+ Faster in swiching tabs.
+ Can play embedded MIDI music.
- No skins yet.
Safari
+ Very small and efficient at ~150MB VSZ. Mozilla based browsers are ~400MB VSZ.
+ Better anti-aliasing of small fonts.
- Slightly slower in rendering.
- Can't play embedded MIDI music.
Firefox
+ Uniform experience if you also use Firefox on other platform.
+ A lot of cool skins available.
- No emacs keys on URL field.
- Ugly form widgets.
I was immediately turned off by Firefox. I honestly don't know why people use Firefox on Mac. It's a decent browser on Linux and BSD, but somehow Mac port got pretty awful.
It was a close call between Camino and Safari. I really liked the fact that both the resident size and virtual size of Safari are quite small compared to Mozilla based browsers. Plus, small fonts on some of the web sites are anti aliased only on Safari! I don't know if I can change fonts on Camino to get anti aliasing from OS or not. Anyways anti aliased fonts look a lot more pleasing than standard fonts.
Then I started experimenting with multiple tabs. I thought Camino was faster to respond when changing tabs, opening documents in a new tab, and so forth. My browsing habit involves a lot of tabs, so it was a big deal for me. Also, going back and forth in the history was faster on Camino. The other browsers would at least connect to the server to validate the page, resulting in a bit of delay. Camino was more aggressive in caching and it was faster going back and forth.
The last criteria was the ability to handle embedded MIDI music. Camino handles some of html objects better than the other browser.
I'd say give Camino a try. Support open source native OSX application.