All modern browsers now have RSS Feeds autodiscovery feature: if you use IE7,
Firefox, Opera etc. when you reach a site that as an RSS feed available, an icon
shows you that you can subscribe the feed.
But... what icon? The old RSS orange icon is not the best choice for a
universal symbol, so the Microsoft RSS
Team about two months ago asked
the community what they think about a possible standard icon for feeds.
The possible choice was undoubtely interesting, but I remember that some of
us asked them to try to have a standard between browsers: a must to do is to
have a universal symbol to recognize a feed (I was a supporter of the icon
number 4).
Result? Between this competitors:
THE WINNER
IS
Do you recognize this symbol? I think that if you are a Firefox user
the answer is YES. 
The reason of this choice is well explained in
this
post. I want to put in evidence this sentence:
"I'm excited to announce that we're adopting the icon used in Firefox.
John and Chris were very enthusiastic about allowing us (and anyone in the
community) to use their icon. This isn't the first time that we've worked with
the Mozilla team to exchange ideas and encourage
consistency between browsers, and we're sure it won't be the
last."
Thanks guys, this is undoubtely the best choice you could take...