Google is onto something here. There are so many useful apps running on browsers these days (many of the best from Google), that deskbound operating systems are getting less relevant all the time. Google is taking this idea a step further, where the browser does almost everything you'd want to do on a computer, but does it better, making whichever operating system you're using unimportant.
Check out Google's excellent comic explanation of the product here. Chrome is a free download for PC thus far, and a Mac version is on the way. Might be worth a try.
UPDATE: Download Google Chrome here.