Justin Van Patten of the BCL (Base Class Library) team provides a rundown of what's new in the BCL with .NET 4 Framework Beta 2, in addition to what was included in Beta 1.

This post describes in detail how calling to DateTime.Now actually causes the CLR to box an integer (4 bytes) during every call. This could seriously hurt performance for applications that may attempt to reduce dynamic allocations to a minimum (in order to reduce the number of induced GC collections...

Description and extension of one of the less-known classes - AppSettingsReader to read application settings as typed and nullable values together with explaining an undocumented feauture of the class - "(None)" used as value to force to return null.

.Net Base Class Library

An msdn article about the upcoming System.Adding namespace in the Base Class Library (BCL), available in the next release of Visual Studio® (code-named "Orcas"). This is the first one. Check the first one too: http://www.dotnetkicks.com/clr/NET_Application_Extensibility_article_about...