News backends allow other sites to see what's going on on your site. In fact, sites like the Daily Rotation consist of nothing else than news feeds gathered from various sites.
Ofcourse, we couldn't stay behind and ignore this, especially, seeing that people actually used our old feed.
Feeds exist in various formats. We currently only use RSS 0.91, primarily because I am too lazy to scope out the other varieties. Yes, I am quite aware it has long been superceded.