Feedburner, or Google Feedburner
FeedBurner provides custom RSS feeds and management tools to bloggers, podcasters, and other web-based content publishers, including the ability to manage RSS feeds and track usage of their subscribers. It also Integrates Drupal with the services provided by Google FeedBurner. Currently this module provides the means to redirect requests for your site's feeds to user-specified/created FeedBurner feeds.
Services provided to publishers include traffic analysis and an optional advertising system. Though it initially was not clear whether advertising would be well-suited to the RSS format, authors now choose to include advertising in two-thirds of FeedBurner's feeds. Users can find out how many people have subscribed to their feeds and what service/program they subscribed with. Published feeds are modified in several ways, including automatic links to Digg and Delicious, and “splicing” information from multiple feeds. FeedBurner is a typical Web 2.0 service, providing web service application programming interfaces (APIs) to allow other software to interact with it. As of October 5, 2007, FeedBurner hosted over a million feeds for 584,832 publishers, including 142,534 podcast and videocast feeds.
Some technical problems reported using Google Feedfetcher service.