I recently switched to using Camino as my main browser on the mac as it's so much faster than firefox. The only downside is that even with all of the add-ons that are available for Camino, I still need Firefox when it comes to debugging javascript or general web development. However, for now I can live with that, Camino and firefox are my dynamic duo. Check out the latest version (1.02) from caminobrowser.org.