As we’ve mentioned previously, the .NET ThreadPool has undergone some serious renovations in .NET 4, improvements on which the Task Parallel Library and PLINQ both rely.  Erika Parsons and Eric Eilebrecht are the PM and developer on the CLR team for the ThreadPool, and they’re featured in a great new Channel9 video covering the .NET 4 ThreadPool and what’s new.  Check it out.