One of the reasons why so many Trilogy alums have gone ahead to found their own startups is because Trilogy University in itself encourage entrepreneurial thinking. New grads who had joined Trilogy were given opportunity to form teams and pitch new business ideas to the CEO. Irrespective of the fact if the CEO liked the idea or not, you could go ahead and work on it. The goal somewhat ( maybe similar to YCombinator) was to have a working prototype with real users live by end of 3 months. And then the whole team decided which ideas were success and worth pursuing post the training program.
It seems like a very non-scientific sample, but still interesting. Google versus Yahoo was a surprise, but perhaps Yahoo also has incented more people to leave over time.
I'm pretty sure my next move will be to my own startup, as that would be the only place that might offer a better work environment and better opportunity for learning and growth.