Apple has announced that it will release a SDK for the iPhone to third-party developers by February 2008. This should dramatically increase the number of applications available for the device and the opportunities to create applications.
However, this will make the device more open to anti-virus and malware attacks (CNET News.com).
An issue with the device is that it is tied to an individual network provider (BBC) in each country. This could cause issues if a company's corporate mobile network account is with a different network provider.
This change may be an incentive for some people to switch from a Microsoft Windows Mobile device. Although this is well established with applications already developed, and multiple types of devices are available that range from mobile phones, pocket PCs, and PDAs.