Performance is something we take pretty dang seriously on WCF. I had the privilege of wearing the Performance PM hat during the last few milestones of WCF v1, so I got an up close and personal introduction to all the work that goes in to squeezing every last bit of performance possible from a bigtime server stack. I wish I could say I was responsible for the fantastic performance we have in the product today, but that honor rightly belongs to every feature developer on the team -- great perf is something that's baked in from the ground up, and it takes a commitment from every single person involved in the code to make a stack perform to its fullest. Of course, having the SWAT team of BobDimp, ErikC and their roving band of brianiacs didn't hurt either :)

The reason I bring this up is because we release the .NET StockTrader application today, which is an end-to-end real-world app that stacks up WCF 3.0's performance against Websphere 6.1. I'm pretty stoked about the summary results:

• .NET 3.0 hosted on IIS with an Http binding and XML encoding offers 124% better throughput than the fastest WebSphere/EJB Web Service implementation tested; and 46% better throughput than the JDBC (no entity beans) WebSphere implementation tested.
• .NET 3.0 self-hosted over Http/XML offers 225% better throughput than the fastest WebSphere/EJB Web Service implementation tested; and 113% better throughput than the JDBC WebSphere implementation tested.
• .NET 3.0 with binary encoding over a TCP binding offers 488% better throughput than the fastest WebSphere EJB Web service implementation tested; and 284% better throughput than the JDBC WebSphere implementation tested.

Gotta love going fast.