Apple might be the most innovative product development company ever. However the iPhone is ultimately a 'lifestyle' phone and there are several reasons why it is already being migrated AWAY from by business users. Blackberry Storm has matched iPhone in new sales (mostly because it has a better typing experience) Mobile offerings from both Google (Android) and Microsoft (Windows Mobile 7) are about to release phones with functionality that has to be seen to be believed. Having worked on mobile applications for several years, I've seen first hand just how much the iPhone's swipe user experience and apps store model have influenced other manufacturers. However, unless Apple is able to license unified communications technology from one of the major players in email (Cisco, Microsoft or an emerging Google) the iPhone will become increasing LESS popular in the business space. Apple is likely building its own unified communciations system because it is having a hard time partnering despite approaching a critical mass of users.

Real Estate will likely be one of the last industries to cross over, because brokerages don't like to invest in technology and agents don't like being tied to broker email. But even real estate professionals will migrate to mobile devices with just as many apps, a great user experience, a real keypad, ability to open lock boxes and full integration with their PC. In the end, most email systems use Outlook. Microsoft has a HUGE built in advantage and they're using dominance on the desktop to gain dominance in cloud computing. (where mobile is one of many access points)