So yesterday I mentioned how email was one of the killer game changing features on the iPhone. Well its true, Apple partnered with Yahoo to offer free “push” email. What does this mean? Well basically RIMM is in trouble. Why are people going to pay $30/month for blackberry service if yahoo is giving it away for free? Push email is the killer app that got blackberries to be nicknamed crackberries.Actually this move is two-pronged, it shows that Yahoo realizes mobile is the way to fight off google’s attempts to steal their mail customers, and it also allows yahoo! mail to become something more widely used than for just spam email folders. Now the big question: will yahoo search marketing be able to monetize yahoo mobile mail??? Second killer question, can they deliver geo-targetted ads via gps? that would mean yahoo would be increasing their monetization opportunities dramatically, and give them a better than fighting chance against goog.