Using the Google AJAX Feed API, a developer might:
* Display a dynamic blogroll on a personal homepage
* Display recent photos from a public Picasa Web Albums feed on a blog
* Plot a feed of news events on a Google Ma
Bret Taylor will feature this new API today at the O'Reilly Web 2.0 Expo in a talk titled, "Who Needs Server-Side Code? AJAX APIs and Product Integration 2.0". You can already see documentation and samples online here.
This API supports several feed types, so you really don't have to worry about what format the feed you are consuming is actually in. This list includes:
From what I can tell by scanning through the terms, you must only develop services that are made accessible to end users without charge. Also, there doesn't seem to be any restrictions as to the number of requests you can make using this API -- which is good news for owners of high traffic websites.