There is a mojor difference between asp.net 2.0 and 1.1 paging model. In 2.0 the aspx markup file and code beside class compiles at same time due to the nice feature partial class.The compilation model produces a comfortable coupling between the declarative markup and the class in the code-beside file. This is ‘vertical coupling’.
In 1.1 there is unwanted coupling between types in the code-behind files. This is ‘horizontal coupling’. Instead of using a layer of indirection, like an interface, base class, delegate, or event, types in the code-behind files can reference each other directly and produce brittle code.
So definitely 2.0 compilation model is better thean 1.1 compilation model.
Microsoft has released Web application project Add-ons same like that in ASp.NET 1.1.Please check y previous post.