The site is still in the early stages, more features are coming in very soon. Some geeky info: powered by ASP.NET MVC, S3, RDS, EC2, CloudFront and soon, Redis for real-time analytics (currently a custom in-memory data structure). Backend was implemented in around a week of non-stop work.
We've been using FeedBurner since 2004, and were huge fans of one of the coolest startups to come from our hometown, Chicago. We also know what it means to have hundreds of thousands of subscribers, our own feed has over 600,000 subscribers constantly making requests for content (don't ask). As the blogpost explains, we would love to take this further and delve into the intricate world of feed indexing but want to take the time to gauge demand and get a feel for the bigger picture. Feedback is most welcome.
Sample "prettified" feeds for those so inclined, ranging from original feeds that provide full content, brief summary, to titles only: http://feeds.feedsnap.com/neosmart http://feeds.feedsnap.com/bbcnews http://feeds.feedsnap.com/hackernews