"Btw: At Startup school, a guy from Google asked us about our startup and what we were doing, etc. It was clear they were looking for ideas there."
That sounds more like an interested hacker from Google who was genuinely curious about your project (like everyone else there), rather than a planted corporate development spy itching to report his scoops to home base.
Actually, the guy seemed more like a manager/business type than a hacker. The first thing I asked him was "are you spying for Google", and he hemmed and hawed actually. He gave no indication at all that he was interested in doing a startup himself, but wanted to figure out what we were doing.
Google doesn't have managers! Everyone there is 10 feet tall, types 200 words a minute, codes in a new version of Lisp called GLisp and can beat up Chuck Norris. You must have been mistaken.
That sounds more like an interested hacker from Google who was genuinely curious about your project (like everyone else there), rather than a planted corporate development spy itching to report his scoops to home base.