[Coda]

Firefox uses lots of memory too. In fact, both browsers will happily consume as much memory as they can get their hands on in order to try to make things faster -- they'll hold pages you've navigated away from in RAM for a while so the back button is faster (and in fact some pages have code on them that REQUIRE the browser does that) and speculatively preload stuff that they think you're GOING to look at soon.

For Chrome, I recommend "The Great Suspender" extension if you want to change that behavior. The extension makes tabs you haven't looked at in a few minutes unload themselves so they're not using up much memory or any CPU time. You can click on the suspend notice in any tab to make it reload itself back to where you were before. For pages that do live updates (Twitter, for example) you'll want to whitelist them so they can keep running in the background.