There is definitely a great divide on whether to keep an idea secret or not. Locations and the social circles you are apart of matter quite a bit; I live in SF and work in PA and I'm surrounded by very capable people. I have had ideas stolen that I was in mid process of building, particularly by an EIR's (entrepreneur in residence) who had better resources than I and were able to execute much faster. And it turned out to be a success in the app store.<br/>
For those who say its ridiculous to keep things secret--I think they aren't surrounded by very capable people who are willing to do anything to be successful. Apple, (a pretty successful company), is highly known for keeping their ideas secret. You know why? Because they have burned in the past, just like I have and others around me. Product test as secretly as you can, build a capable product, not an MVP, and hit the market hard!
I'm not sure Apple's a great example. They keep their ideas secret for marketing reasons: they get immense amounts of free advertising by being dramatic about new product launches. And because they burnish their brand by maximizing their number of public hit products. (They also keep some details of incremental improvements secret because it's a highly competitive market, but that's different than stealing ideas for new products.)
In fact, I'm having trouble thinking of a "big new idea" product they did recently. They were years late to the MP3 player and smartphone markets, for example.
Since the idea's out, would you mind saying more about the idea that was stolen?
I don't think Apple is a great analog for most startups, who don't have the time or cash to test and iterate in secret for months. And many of their products that needed real world validation (Ping, Siri) have not turned out great.
