You meant http://www.google.com/reader, right? (or one of several online alternatives). Why would anyone want to read their RSS feeds in a single browser on a single machine in 2010? Do people these days really spend all their online time at a single machine?
When a user clicks on a .rss URL in FF the page is rendered in a human-readable format. This aids the user in determining whether or not the feed is worth subscribing to.
Chrome displays it in plaintext. Now you've gotta import it into your reader before you decide if you really even want to subscribe.
Actually i meant all of the rss reading eyxtension there.
I thought some of them are Google Reader integration and some of them are the standard rss-fetching kind.. never tried one of them, though ;)