Windows Live is a free, ad-supported AJAX virtual desktop. Features include (or will soon include), instant messaging, internet telephone calls, integrated email and you guessed it web feeds.
What is more Windows Live can be extended by the installation of "gadgets" that can be developed by pretty much anyone with the skills. It wouldn’t suprise me if the next thing you should be focusing on after adding an RSS feed to your site is the development of your own gadgets.
That means all the big players (Yahoo, Microsoft and Google) now provide virtual desktops built around delivering web feeds to peoples start pages. Combined with the live bookmarking function built into Firefox and the upcoming I.E. 7 makes an RSS feed as important as your newsletter email sign up form.