Given how much of what we do in my team is related to the web (ADO.NET Data Services, System.Xml, etc.), Mix is one of the events I look forward every year, both to share some of the stuff we're working on and to hear from attendees who are building real-world applications.
If you are around, feel free to drop me a line if you want to chat. I'll be there through the whole event, and will be doing two talks on Friday, one on the Entity Framework and how some of its new features can make life easier when writing web applications, and another one on ADO.NET Data Services where I’ll discuss how to build RESTful data-centric interfaces and what’s coming in the future of Data Services.
-pablo