This session might be a good developer–centric view on the up–and–coming aforementioned technologies. Personally, I’ve used all three technologies on different levels.
LINQ is a fascinating new way to query, retrieve and interact with data. I’m using LINQ for XML (formerly known as XLINQ) for a project and I absolutely love it! No more cumbersome XPath or verbose serialization classes. I believe Microsoft is truly committed to this technology as well. Several weeks ago, I posted a question on the LINQ forums to which Anders Hejlsberg answered himself.
Admittedly, WCF is the least exciting technology in the roster as it has been out the longest. They’ve cleaned up some of the older concepts and made it a lot easier to expose your data in different ways. All of which was previously available in different forms before though.