[ot]

My main concern with WP7 is that it can run only managed code (see http://social.msdn.microsoft.com/Forums/en-US/windowsphone7s... for example).

This means that existing non-.NET code has to be rewritten from scratch to be ported to WP7, while on iPhone and Android it is possible to link native code.

If a developer wants to write the same application on iPhone or Android and WP7, basically no code can be shared. Is it worth it?

[charlesdm]

Native code can be shared on all platforms except for WP7 if written properly.

[ot]

Yes that was my point, Android and iPhone can share code, WP7 can't