but I am doubtful that they'll do much else besides foster Microsoft-centric development of tools and programs
I think you hit the nail on the head there. I honestly think its more of a cultural thing that a strategic one though: whenever Microsoft tries to reach out and diversify, the lower level Microsoft culture makes the whole thing collapse back in on itself. A perfect example is Silverlight. Here is a project where Microsoft had every reason to create universal plugin, a Flash killer, which they alone held the development tools to, as Adobe controls Flash development tools. So they handed it on a platter to the Mono project, who rushed to make the moonlight plugin. But then you install moonlight, and go to the sample sites, only to see that the web devs actually block moonlight because its not Microsoft Silverlight, they won't even let Moonlight try and render it. So Silverlight is yet another thing you can't really install on a site for the world wide web, where you can have an expectation of all viewers accessing the content as you can with Flash.
The relevance of the entire project is diminished by the "Microsoft only" culture of the lower level devs even at the expense of Microsoft. To be honest, I think a dose of open culture may be just what the doctor ordered for these guys, and it may be that the higher ups know it, thus this Foundation. Just a guess. :)