On Krzysztof Cwalina's blog there's an example of what may be coming in the Managed Extensibility Framework, a framework for dependency injection, naming and activation, and duck typing. Looks like it could be interesting when released.

While on his blog, I got to reading some of the older posts:

• The second edition of Framework Design Guidelines is in the works, and may be out by the end of the year.
• The Framework Design Guidelines Digest v2 is available for download in PDF format.
• How to Design Exception Hierarchies gives good advice on when to create new exception types, and when to reuse existing types.

There's good stuff buried in the archives of Krzysztof and Brad Abrams blogs.