Okay, I hate to be a Negative Ned here, but I'm firmly in the "trust but verify" camp when it comes to Microsoft and open source. Yes, a new CEO and other changes may be helping Microsoft to adjust to living in an open source world. But change never comes easy or fast in such a large organization, so I think the jury is still out on whether or not Microsoft has really changed for the better when it comes to open source software.
Also, I've never forgotten the company's "embrace, extend, extinguish" strategy that they used in the past to destroy competitive software products. That alone is reason enough to keep a wary eye on Microsoft's involvement with any open source project. Perhaps the company really has changed, but maybe it hasn't. I think it bears watching for at least another few years to see if enduring change has really set in or not.