Fundamentally, the act of crowdsourcing is instead of hire a singular firm, agency or consultant a challenge is put to a group of people. Those people work individually or as a collective to accomplish overcoming that challenge; therefore, you harness more brainpower around the project. Additionally, people/firms that participate are often experts in unrelated things to your challenge and therefore bring a fresh and untainted viewpoint that you might not get if you hire a shop that specialized in "X."

Jeff Howe in 2006, a writer at that time for Wire Magazine coined the phrase "crowdsourcing." If you think of the what it means – getting/creating something from mass opinion/expertise, there's a lot more than this term that you can point at. Reviews, ratings and even your works suggestion box could theoretically apply as well.

You've seen crowdsourcing in effect for years and you've probably not realized that (by definition) that's what it was. Websites like wikipedia, flickr.com, and TripAdvisor are all types of crowdsourcing. Clearly, not all crowds are right for all challenges. While the crowdsourcing is a type of mass collaboration, it is also done typically within a given interest. What, again, makes this powerful is on both sides of the fence. It allows people that may or may not be within your perceived needs working on your challenges, but often it's FAR less expensive.

Many crowdsourcing companies have adopted a loose model that goes something like:

1. A company (ACME) needs an advertising campaign to successfully launch product "X"
2. ACME does not have the money to hire a BIG agency
3. ACME reaches out to a crowdsourcing firm
4. ACME posts it's needs, notes and direction to the firm
5. People/Groups/firms return to the post with a possible direction
6. ACME chooses five to pursue their thinking (these five get paid a small amount for making the cut)
7. The Five turn in more refined creative and possible directives
8. Two or Three are chosen to refine the thinking/budgets further  (these three get paid a larger amount for making the cut)
9. A finalist is selected making the most as a project is there's too develop

What this allowed ACME to do is not only see a lot of great thinking for a reasonable expense, but it kept everyone in the process honest as the reward was there until the end. It also gave ACME a better understanding on what and how people price various techniques and thinking. The fact that crowdsourcing is changing the way we do things is simply an education in the online process where people of all kinds "like" certain things, "follow" other things and communicate their ideas and emotions utilizing various technologies.

What you're also seeing are smart companies letting their customers or their "crowd" participate in the development of their product and or services. You see threadless.com asking for customers to the vote on the t-shirt designs they like the most. Ergo, that is what is ultimately manufactured, which in turn is someone self-fulfilling for threadless as the people that voted for a design are predestined to want or consider purchase. We can even go as so far as to look at American Idol as entertainment crowdsourcing. You vote for the singer you want to stay and don't for those you want to go.

The mighty wiki says: "Crowdsourcing is a neologistic compound of "crowd" and "outsourcing" for the act of outsourcing tasks, traditionally performed by an employee or contractor to a large group of people or community (a crowd), through an open call.

For example, the public may be invited to develop a new technology, carry out a design task (also known as community-based design and distributed participatory design), refine or carry out the steps of an algorithm (see human-based computation), or help capture, systematize or analyze large amounts of data (see also citizen science).

The term has become popular with businesses, authors, and journalists as shorthand for the trend of leveraging the mass collaboration enabled by Web 2.0 technologies to achieve business goals."

What business models can we anticipiate it effecting? Probably more than you think: 

Advertising:
http://adhack.com/
http://www.geniusrocket.com/
http://zooppa.com/

Great Links:
http://www.innocentive.com
http://www.kickstarter.com/
http://www.crowdsourcing.com
http://www.suggestionbox.com/

Usability & Testing:
http://www.usertesting.com
http://www.goosegrade.com/
http://www.utest.com/
http://www.ideascale.com/

Graphic Design & Writing:
http://www.crowdspring.com/
http://99designs.com/

Market Research:
http://www.mob4hire.com/

Predictive Modeling:
http://inklingmarkets.com/

Naming:
http://namethis.com/name_this/

Ideas submission:
http://www.quirky.com/

For Video Creators:
http://www.poptent.net/