I finally downloaded the iPhone SDK and I’ve been exploring it all day. However, the license has some serious restrictions which may affect our ability to develop our product for the iPhone. In particular:
3.3.1 Applications may only use Published APIs in the manner prescribed by Apple and must not use or call any unpublished or private APIs.
3.3.2 An Application may not itself install or launch other executable code by any means, including without limitation through the use of a plug-in architecture, calling other frameworks, other APIs or otherwise. No interpreted code may be downloaded and used in an Application except for code that is interpreted and run by Apple’s Published APIs and built-in interpreter(s).
It also appears that we won’t be able to develop an invisible background application without violating the license.