Surely those that are currently in the gambling industry offline would enter the online world if/when it becomes legal. However, I don’t see too many big portals (Google etc…) moving into the gambling market – Not directly anyways. I’d imagine any player playing at ‘Google Casino” that loses might potentially stop using their other services.
I think we’re worth more to Yahoo/Google/Myspace/Etc in advertising dollars and service users than we are as casual online gamblers. I think non-industry companies would be risking quite a bit by trying to enter a market that they really have no business being in – Especially since it could dramatically hurt their image.