Bloglines recently announced web services and an API for developers to interface with their service.

At the time of the announcement, FeedDemon, NetNewsWire, and BlogBot were listed as applications that planned to make use of the web services.

From the press release:

Bloglines Web Services address a key issue facing the growing RSS market by reducing the bandwidth demands on sites serving syndicated news feeds. Now, instead of thousands of individual desktop PCs independently scanning news sources, blogs and web sites for updated feeds, Bloglines will make low-bandwidth requests to each site on behalf of the universe of subscribers and cache any updates to its master web database. Bloglines will then redistribute the latest content to all the individuals subscribed to those feeds via the linked desktop applications — FeedDemon, NetNewsWire or Blogbot — or via Bloglines’ free web service.