I believe that during the process of designing a product, the opinions of the people in your target group are very important. We’ve been researching OpenIDEO which is definitely an online community that I would use if I had a design challenge. It would give me the ability to post questions about the design and receive opinions from all over the world.
Taking a look at the other groups I would also surely use Facebook, although OpenIDEO allows me to communicate with everyone and Facebook only allows me to communicate with my friends. This is fine but their opinion might be more biased towards one place’s opinion, since most of my friends on facebook are Dutch or from my home country. While designing I think its very important to keep many diverse opinions in mind and try to collaborate them so that the product can be for as many people as possible.