Microsoft's recent acquisition activity brings to it a lot of Java-based software, expertise, as well as a large Java-focused customer base.
In January, Microsoft announced its intent to acquire Fast (www.fastsearch.com), a company that sells a Java-based search engine to OEM partners (see http://www.informationweek.com/showArticle.jhtml?articleID=205602306&queryText=Fast+Search). Today, Microsoft announced its intent to acquire (http://www.informationweek.com/showArticle.jhtml?articleID=206401789&queryText=danger) Danger (www.danger.com), a company that sells a Java-based platform for mobile devices, such as the T-Mobile SideKick (see http://www.t-mobile.com/shop/phones/Detail.aspx?device=154e9bca-a74c-4299-99eb-48a1159c922b).
Presumably, Microsoft is aiming to take Google head-on in both the enterprise search space, and the mobile platform space. That makes sense, given the tremendous growth and potential in those areas. Never mind the possibilities of new markets around the end-to-end integration of the two. Imagine the up-side of a combined enterprise middleware, desktop OS, and mobile OS strategy with an integrated hardware platform!
The interesting part of this is the amount of Java code that Microsoft acquires with these deals. All of the enterprise code in Fast's products is based on Java, along with the Danger mobile platform. This also brings with it an installed base of integrated OEM and third-party Java-based applications, and the associated Java developer communities. In my opinion, Microsoft has no choice but to support and enhance this Java-based strategy. What else can they do; switch to C# and alienate both companies' customers and developers? Doing this can conceivably destroy the value and hence the strategy behind the acquisition of these companies in the first place.
Instead, what I think we're witnessing is Microsoft's embrace of Java to gain traction in areas of the Web 2.0 world where it has not been able to get to with .Net and C#. I, for one, am very interested to see how this will play out; I would expect this to spark the beginning of a new stage of Java growth in the industry.