My view on 'crowdsourcing'.

Crowdsourcing is IMO much similar to common scam. Fraudsters are crowdsourcing they money. They make a business proposition which almost nobody would accept - to a large group of people. Very small percentage of whom make a decision mistake - i.e. get conned.
Same goes for most crowdsourcing. A crowdsourcer is making a business proposition - typically to write some software or make some design with non-guaranteed AND small pay - which almost nobody would accept (not even mythical people from 'third world'. Don't forget that both computer and internet connection are more expensive in developing countries). But with 'crowd' of hundreds thousands passing by, it is guaranteed that a few make decision mistake and accept. Bottom line is, both scammers and 'crowdsourcers' are profiting from rare psychological conditions and decision mistakes in a huge group of people.

Some crowdsourcing-like businesses could be different however. Innocentive, for example, where its mostly industrial chemistry, not programming, and rewards are quite big, good for few weeks work at $100+ per hour. Some of those problems might be nice for industrial chemist with relevant obscure expertise who can solve it quickly and win with no competition. I would call that expert sourcing; the industrial chemistry problems are of different league than programming and software design entirely and the spec work approach makes lot of sense when you really don't know if the problem is even solvable - and makes no sense what so ever if its mere matter of spending time. (I'm no chemist though sometimes I wish I were doing chemistry or physics for living)