The mapping tool as of now only includes translations for Network/Internet, User Interface, and Data Management related programs. Audio/Video, Graphics/Animation, Performance, and Security related API translations will be added at a later time.
It’s important to note this tool is just a starting point for developers to learn about the WP7 platform and by no means will include a translation of all API’s between the platforms.
This mapping tool seems to be a very blatant attempt by Microsoft to encourage the porting and migration of apps and developers from the iOS platform to the WP7 platform. This is great news for developers looking to expand to other platforms and shows how far ahead Apple is in terms of market share in the mobile computing world. WP7 is a vastly improved mobile OS (compared to previous Windows offerings), but Microsoft continues to neglect their products. WP7 hasn’t seen any major updates since its release (the first one was a beautiful train wreck of a mess).
All problems aside, this little tool and Microsofts partnership with Nokia looks to help WP7 recruit more potential developers. More competition in the mobile market means we’ll only see more innovation on everyones part. Hopefully.