I thought that WordPress blogs automatically created feeds... The way I've got it set up it does.
I thought feedburner was more to promote your blog, as you can in, say Technorati and other sites.
What I'm not sure about now is how you'd track how many readers you have, given that people have so many ways of subscribing to feeds (e.g. through bloglines, their browser, Google Reader, etc., etc, etc, )
