Go to feeds.my.aol.com. Yet another web-based aggregator. Test it the way you’ve tested dozens before, by typing the URL for your feed in the text input. Wups, not found. Now, try typing in the URL for your blog’s front page (assuming it supports autodiscovery).
Now that is some serious support for autodiscovery, and unwillingness to go down the rathole of how to link three-letter-icons to incomprehensible spews of XML. Either that or it’s just broken in beta. But I love the thought of an aggregator so unwilling to get its users involved in the whole “here are my feeds in five different formats, you choose one without any idea why there are so many” that they flat out refuse to let their users enter a feed URL directly.