I read an interesting quote from Annette Nibley (one of my favorite advaita teachers. Her site is http://whatneverchanges.com .)
She writes,"Believe this: if a book or personality is wildly popular with the public, it is full of junk ideas that appeal to egos and sell more books."
Why are some teachers more popular than others? Why has non-duality been less popular than say yoga or the secret or ...(pick Oprah's favorite guru this week).
Is it what Annette says? To be popular it must appeal to the ego, the ever striving, never satisfied false identity.