I love Feedburner. If you're a blogger, it's your best friend. They help you track your readers, they help you ping all the big blog search engines when you've made a new post, and they help you add all the cool little Digg and Delicious links at the bottom of each post. I've never had a problem using this service, and as my blogging skills get better, I can always find more sophisticated feed tools to make my blog better. Feedburner seems to stay a step ahead of a blogger's needs.