"One of the adjustments to make when moving from ASP.NET 1.1 to 2.0 is how to produce debug and release builds. "
[...]
"Here is the most important concept to come to terms with in 2.0: Visual Studio 2005 knows nothing about compiling a web application. In 1.1 VS built the code-behind and ASP.NET built the web forms. In 2.0 Visual Studio 2005 delegates all compilation responsibilities to the ASP.NET platform. "

Qui il post intero di Scott Allen sull'utilizzo dei nuovi strumenti Publish e Web Site Deployment (WSD) in Visual Studio 2005.