I use RSS all the time, mostly via Firefox's subscribe-to-page feature. I've considered looking for a native-client feed reader, but my understanding is that most sites don't provide a full-text feed, which defeats the point.

I dislike that it's based on XML, mostly because, even more so than JSON, XML is actively hostile to humans. It's no less useful for that, though.

So far as I know it doesn't handle reply chains at all, making it a sub-par fit for content that spawns discussion. I may be wrong about that. I still use it as the best available method for e.g. keeping up with LW.