Microsoft through out the past as seen by many has been a strong opponent to the Open Source community, as it being one such company who believed 100% in the commercial aspects and development of software and related infrastructure (including services, support, add-ons and extensions etc.). However, along with the drastic change of perception, where clearly marked development models and interactions of software are now void, and rather moving towards a more globalized system including involvement of varied disciplines, Microsoft too have decided to make their move into the Open Source territory.
The change might seem rapid and sudden to some, but not to those who've been having a careful eye of the recent changes in the industry (more info here). My two previous posts (Microsoft Funds ASF, and WSO2 @ Tech.Ed 2008) of how Microsoft approached true Open Source provides a solid justification to this fact. The greatest question presented by many is whether 2008 is the turning point which breaks the prolonged and greatly spoken barrier between Open Source and Commercial worlds of software.
I was amazed to see this post which introduced the first ever committers from Microsoft to the Apache Software Foundation, who'd perhaps be the first ever contributors to broader Open Source in a manner that is publicly aware. In my personal opinion this unfolds a new era in the entire industry of IT, Systems and Software. The Apache Software Foundation is also a much admired community by many due to its openness and true contribution to create a world of freedom to use software unlike most other entities that promote the same.
The entire Open Source community would un-doubtfully be looking forward to further involvement and contribution by not only Microsoft, but also several other commercial strongholds.