What matters is that the items Apple hangs the "open source" sign on are the fundaments. MS not so.

e.g. Apple has open sourced the core OS and WebKit (Safari's html engine). MS has open sourced neither.

Nokia uses WebKit. Android does. etc. Nobody uses IEmobile unless forced to.

Oh, and didn't MS actually pull the iStore scam with Zune, and only lost due to low markedshare of the Zune and being unable to come to proper terms with the RIAA because MS was too focused on DRM?