Extracted 05MAR2012 from http://en.wikipedia.org/wiki/Crowd_funding
Proponents of the crowd funding approach argue that it allows good ideas which do not fit the pattern required by conventional financiers to break through and attract cash through the wisdom of the crowd. If it does achieve "traction" in this way, not only can the enterprise secure seed funding to begin its project, but it may also secure evidence of backing from potential customers and benefit from word of mouth promotion.
Against these advantages is the requirement to disclose the idea for which funding is sought in public when it is at a very early stage. This exposes the promoter of the idea to the risk of the idea being copied and developed ahead of them by better-financed competitors.