Slower in benchmarks blah blah, but for the power of its extensions which I find invaluable and essential it's still the best, plus with every other computer be it Windows, Linux never mind a Mac for a cross platform user like me it's sync knowing your data is not going to be mined is also top notch. With cloudy tabs for OS X I can have the iCloud bookmarks too.
Chrome has its uses on OS X - for flash! Safari occasionally gets used for the keynote video streams
Safari and Firefox.
Safari is fast and the integration is amazing but ive always used Firefox and it has a nice refined feel to it despite being slower and the pluggins etc.
Its handy having 2 browsers for multiple accounts on the same site ie Paypal, Ebay etc.