The Founder Paradox - should you share your idea?
ycreject.com
ycreject.com
I'd be willing to wager that more projects have been killed from this sort of paranoia-fueled secret keeping than by people stealing ideas.
If you share it with someone that has the resources to build it faster than you, it's just going to create headaches for you in the future.
So, it's a good idea to share the generic idea, but not the specifics.
One of the businesses I'm running now (which is profitable) spawned from an idea I saw on a message board about 6 months ago. I knew the original implementation of the idea would never work and I improved on it. It's a direct competitor to the original person that posted it.
Obviously I'm not telling you to pull out your full spec and implementation roadmap to discuss with everyone on the street. But you should be willing to share the core idea in a way that anyone can understand. The "what", not the "how", essentially.
You can always divulge more if someone shows interest in helping you out, but you have to garner that interest by being willing to tell them something.
Your network will start working for you only if you share your idea. You will be surprised how many people come of the woodwork to say, "Oh, I heard you are interested in this space - I have this person you should talk to; I read this report on your market; I have this angel you should meet..."
You are afraid someone will steal your idea? Don't flatter yourself so much. You can be sure there are 5 other people other there at the same time who have a very similar idea. Ideas are cheap; it is only execution that matters. And there is no way you can best execute on your idea without getting all the feedback you can get and finding all the resources your network can provide you.