The orange icon, which in Firefox 1.5 appears at the far right in the address bar, designates an RSS feed, will be used by IE 7, said Jane Kim, the program manager for RSS on the browser's official developer blog.
After meeting with Mozilla Corp. developers, said Kim, "we all agreed that it’s in the user’s best interest to have one common icon to represent RSS and RSS-related features in a browser."
The icon will be used in IE 7 in much the same was as it's now applied in Firefox; as an indicator in the address bar when the browser's on a page with an RSS feed. It will first appear in the public beta, which is expected in the first quarter of 2006.
This isn't the first time that Microsoft and Mozilla have cooperated on browser development. In November, the two companies joined representatives from Opera and Konqueror to talk about ways to warn readers of possible phishing sites.