Firefox is a* bloated piece of crap*.
Internet Explorer is a backdoor for the Chinese government.
Safari is alright but seriously lacks in features (extensions, history)
So, for the past few weeks I have been using Chrome; Google just released the developer build of Chrome which will run extensions on OS X (4.0.295.0 as of today). I have to say – this browser is getting pretty damn good. Here is a specimen with a few tabs and extensions open on my machine.
With a few extensions and a some tabs open Chrome feels more responsive than Firefox, actually works unlike IE and has more functionality than Safari. Chrome does crash a bit more than any other browser; however, it is very nice to have the crash isolated to one tab and not the entire browser.
At this point, I have to say, in my opinion, Chrome is winning my vote.
The development channel for Chrome is available here.