IETF standards have a history of longevity, and I suspect this format will be around a very long time.
What is it about RSS that is broken and what would you like to see replace it?
Atom: see http://www.intertwingly.net/wiki/pie/Rss20AndAtom10Compared for details but it basically boils down to RSS having gaps and inconsistencies which are compounded by the spec being essentially fossilized and David Winer being famously difficult to deal with.