I'm thinking about integrating some sort of (Atom) news feed into a shopping system, but I'm not sure how to go about it, except that I want the URIs to be the same for each representation (HTML, Atom). Let me explain through an example:
Let's say you have some arbitrary product listing page (red shoes for women). What would make the most sense to have as a news feed for that kind of URI?
Should the feed always contain all the matching products and only update the date on each feed entry if something (like price or availability) has changed? Would I have to update the entry's unique ID, too? Or should the feed only contain actual changes to the data, like "Product X now costs Y.YY"?
This also matters because the first way, I wouldn't have to store/persist feed entries, and that sounds good to me. But in the end it matters to me more what the best use for end users would be.