IE8 beta and Firefox 4

[ConkiZz]

FF is much bettre than IE, it's just the tuth

[chip19]

Firefox in general on Mac is terrible if you use the builds available on Mozilla's site. The builds optimized for your certain architecture are MUCH better. Check this link:
http://firefoxmac.furbism.com/

I build my own from source, but that site has Nightly builds of Firefox optimized for different CPUs like Intel and G4.