Same. It gets the fastest updates, is the fastest browser, is the most secure browser, and is basically leading the way in browser innovation on all fronts.
I use Safari for Mac, really the only reason is I love the top sites feature and I like how it looks when I click one of the thumbnails and it expands into the webpage.
I switched from Chrome to Opera 11 when it came out. I find the speed much faster and enjoy the greater freedom in terms of custom layouts etc. Also really enjoy the ability to mask your browser as FF or IE. Makes running everything possible, something which Chrome didn't have AFAIK (eg I couldn't run Netflix or my university's Java Webmail client).
I use Internet Explorer and Chrome too. I was using IE mainly, but now Im starting to use Chrome more, but for some sites, I still use IE.
Firefox for me. Chrome sometimes, But firefox seems to be the most reliable one for me, though it is a bit slower
I run IE because I work extensively in SharePoint, which is a Microsoft product and as such, works better with IE than other browsers. Chrome is my primary, it is just so much cleaner than FF.