Skeptics may view the Bitcoin concept as revolutionary as search engines or social media but the skeptics are likely to think of Bitcoin as an Altavista or Myspace and imagine there will be lots of competitors that come and go with eventual leaders becoming dominant like Google and Facebook.
Google, facebook, Myspace, are FREE services. People don't need to trust them. Using these services is like having a friend with benefits. Becoming a bitcoin user involves a little more commitment, a little more trust. In some cases, A LOT.
So I propose Bitcoin will not be abandoned as readily as you suggest. Bitcoin isn't a fickle adventure like some long-forgotten internet upstarts. Bitcoin's properties never change.
*cue 80's dance music*
*Rick Astley swaggers in from stage left*
"Never gonna give you up...."