Zach Wilson asked me via Twitter to define crowdsourcing in less than 140 characters. My response:
More people collaborating to create more value with less individual effort than was possible pre-Web.
With room to spare! My twitter handle if you want to follow me there as well: @davidgammel.
C. David Gammel, CAE 
And my reply…
“Interesting. To me, crowdsourcing is initiated by a client and has a underlying motivation for the participant. IMO that is $$$ driven”
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