Every Open Source has a different story; some are created just for fun, some are supported just to trouble Microsoft, even some knows how to make money out of it. But there is no clear pattern on how enterprise has to react to Open Sources.
Fortunately, Eclipse RCP has some great answer for such questions
Eclipse RCP is core engine which makes the fabulous Eclipse Java Editor, this core is important for every desktop application. If you try to build such core it might take years and need hundreds of highly skilled engineers. So the best option is come together and build the core. Today Eclipse initiatives is driven by companies such as IBM, Actuate, BEA, Borland, CA, Compuware, Intel, Iona, Motorola, Nokia, Scapa, Serena, Sybase, Wind River, and Zend
So, the bottom line is simple
1) Open Source is no more about individual programmers, it is new corporate Game
2) Share the common burden and focus on the real differentiators
I am not alone, Sun's Chief for Open Source, Simon Phipps, has raised similar thoughts in the recent Open Source Business Conference
As always, there are some counter views and Simon's response to the same.
Sun "Chief Open Source Officer" on "Open Source"
Simon Phipps on Open Source: Redux

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