A lot of blame can be placed on the tools providers.  The business models have some headroom before RSS is required in the publishing mix.  And the format itself has some inherent awkwardness. 

These are obvious to those of us watching the evolution of RSS every day, but I think there are some other important issues that must be addressed somehow:
  • Maybe the user has too much control.  What kind of people want to take responsibility for managing high volumes of incoming data?  I like seeing new mail in my inbox because someone wants to contact me.  I don't like seeing unread items, though, because that feels like work.
  • More better filters, please.  Where's the PageRank equivilent for ranking items of interest from the RSS cloud?
  • The data isn't pretty.  RSS can be about so much more than headlines.
  • Its social power isn't obvious yet.  Email, IM, SMS and blogging all have specific and tangible social implications.  How will I explain to my mother that RSS can help her connect with people in new ways?
Or maybe it's all a bunch of hoo-ha, and RSS will just fade into oblivion.