Managed Objects' own Jim White wonders if Microsoft will be a “game changer” in the IT management space. In a blog post on this story he comments to the effect “there is little doubt Microsoft’s move will make ripples in the market,” and if Microsoft is truly making a “serious commitment to IT management, there is a high probability for success. That success will likely come at the expense of incumbent vendors – mainly by way of taking market share from the Big 4.” However, he doesn’t seem to think success is necessarily guaranteed as there are “market dynamics and competitive factors that will influence how – and how quickly – Microsoft’s initiative evolves.”

Here's a link to his post: http://www.wearebsm.com/managed_objects/2008/04/microsoft-goes-open-source-a-g.html