Communities For Start-Ups
Technology start-ups don't usually want or need a community. They either want an online customer service channel or they want advocates to promote their technology. Neither requires members to have relationships with each other.
"Building communities on the Internet is a new kind of profession. There are an awful lot of technology companies, founded by programmers, who think they are building communities on the Internet, but they’re really just building software and wondering why the community doesn’t magically show up."
The problem is communities are for people which already use your products/services, not for reaching those that don't (why would people join a community for a product/service they don't use?).
The opportunity is to build a community around a strong common interest/purpose (e.g. seamless photo sharing) and then develop the dream product for that community. When you launch the product, you will already have a dedicated community of people eager to use it. These people are more likely to promote it to others.
Seth Godin defined this best; find products for your audience, not audiences for your products.