The always excellent Tim Anderson, writing for the always excellent The Register, has put together a nice article on the relative success and failure of .NET as a platform and as a Java-killer.
I've made it clear in the past that I'm no fan of .NET and I don't see any clear benefit to our industry by its introduction. This paragraph sums it up nicely:
A long-standing gripe is that Microsoft itself has been slow to adopt .NET. "It will be the framework that Microsoft itself uses going forward" Microsoft's Tony Goodhew told TechEd in 2000. The company, though, has continued to use native code and C++ as the primary development platform for its crown jewels, Windows and Office. COM has never gone away, and .NET developers who want to use new Windows 7 APIs, for example, have to use an interop library to do so.
Seeing as CodeGear/Embarcadero came to the same conclusion when they decided to stop playing catch-up with .NET in Delphi, I can justify my decision never to take our software into the .NET arena.