Two unintended consequences of Microsoft open sourcing:

1. Google Chrome (on Windows) uses the Windows Template Library (WTL) published under the Ms-PL

2. Mono outpaces Java for Linux desktop application adoption. An interesting quotation from the article:

“It is an interesting irony that Microsoft's sponsored technology, which is open source, is allowing developers to be more productive on Linux than other tools for Java and C++ development”

Irony, indeed.