To be honest, I think that ideas on their own are worthless. Its the sweat that needs to go into building something that is a real business that is the difficult part. I agree that you might think that people would want to clone it, but cloning something alone does not guarantee any kind of success. There are hundreds of examples of sites that do very well, where other people have tried to emulate them only to fail. Personally I put it down to a lack of passion on the cloners - its not really their 'baby'. They've not agonized over what to create, how to create it and this probably makes (part of) the difference between success and failure.

Personally I often find it inspiring when people do discuss how much their startup makes. Inspiring on the "I could do it too" scale and sometimes there are good lessons in these stories - not so much this one I would hasten to admit!