As you've seen from various postings to this blog, the Orcas wave of our development technologies is rapidly maturing and is nearing readiness for mass consumption and uptake by our ISV partners. However, I'd like to point out that the June 2007 MSDN Magazine provides a great collection of articles on the topic.
In Orcas, you can expect enhancements to C#, Visual Basic centered around the forthcoming LINQ technology and you can expect the tool support around all the .NET 3.0 innovations (WPF, WCF, and WF) to improve with this release.
Also, you can expect improvements to C++ centered around managed/native code interoperability, UAC, Vista, and MFC (yes, you read it correctly, MFC.) Having worked with a number of ISVs with considerable C++ codebases, this should come as welcome news.
In your spare time, you could check out the CTP builds of Orcas to see this all in action. 🙂