Feedburner is a free, Google-owned service that provides great feed statistics and services to bloggers and other feed publishers.
Here’s how to integrate Feedburner with a self-hosted WordPress blog:
Feedburner
Enable Email Subscription with Feedburner
Not all visitors to your WordPress blog will be familiar with RSS feeds or how they work, while some other visitors just don’t want to mess with using a feed reader. RSS isn’t the only push-delivery method out there: email subscription is another great service to offer to your visitors.
Subscribe to feed