Good they're contributing something back. They should sponsor more developers to work on infrastructure they could integrate into their offerings. Even from their evil perspective, they'd still be able to use their EEE strategy for people foolish enough to buy their non-standard version. They'd benefit from increased innovation and reduced costs as projects get bigger. We'd benefit with components that had financial support to keep improving and maybe get more security review than certain FOSS projects that have never heard of that.

So, it's in their interest to expand their role in open source software whether they intend to play nice or evil. They'll benefit and we'll possibly benefit either way. At the least, quality and innovation should both go up. Microsoft could always use more of those. ;)