One day you get a great idea… You start researching, you start experimenting and in most of the times problems will occur. In history the biggest scientists and inventors also got to this point eventually and I can only imagine what they did to inspire themselves with new ideas, views or knowledge.
Nowadays we have this thing called ‘World Wide Web’ where most of the world has access to and I (we) would be plain stupid not to use it for situations where I find myself stuck. It would be like not using the perfect tool when it lies right in front of you.
So to get this entirely clear: If I had a design challenge I most certainly would join and participate in online communities because what I have seen from platforms such as OpenIdeo and Kickstarter is that they have truly good concepting. I mean even if they hadn’t you would still have the chance to connect to people all over the world (on the same grounds) but they actually assist you and can help you with your project in whole new ways.
Additionally (a little bit off the topic) I think that it should be obligatory for every human being to take part once during his/her lifetime in an open innovation/design project online because I think that even the most unqualified person can mix things up and bring new ideas to the table.