The “pro” part of Feedburner is now free because Google bought the company. I highly suggest you log into your account and turn on the pro features which lets you track more information about your blog visitors.
You get to see things like daily visitor counts, and where those visitors come from, top pages on your blog and top referrers. Sure, you can get that from your Google analytics too, but if you’re a stat fanatic like me you can simply get your rss AND your regular stats in one place now.
Remember, you have to turn this on for each feed you have, and it will require you to put a piece of code in your blog.