HTML5
Adobe Flash, PDF built in
hardware acceleration and WebGL support
Already on its 19th update
Fastest in the kraken, v8, and futuremark peacekeeper benchmarks.
Easy to use
But really, how can you compete with google? They have billions to put into what they make, which is why mozilla will never make firefox as good as chrome. Plus chrome is minimalist, which makes it crazy fast.
Chrome. I like its simplicity. Unfortunately, I've had a few bugs with it, but Firefox is just too... I don't have a word for it. It's not simplistic, it doesn't suit my needs, and Chrome is definitely the faster browser.
Plus, it has integration with Google which could be good or bad, depending on how you use it.
But recently i've found that safari is shit because when it plays videos it sometimes freezes, whereas on firefox when I am watching videos it never freezes. I never really bothered looking into chrome.