RSS/Atom will have a hard time becoming popular as long as developers remain biased against anything to do with XML. If someone reinvents Atom but worse using JSON, there might just be a chance.
I have long hoped it would pick up steam with the JSON-ify everything crowd, just so I'd never see a non-Atom feed again. We perhaps wouldn't need sooo much of the magic that is wrapped up in packages like feedparser² to deal with all the brokeness of RSS in the wild then.