lets just put it this way

In old ASP you had only limited crappy VBSCript for your pge logic..now with ASP .NET you have full blown VB .NET or any other .NET language to write your logic with..

It is also easier to seperate logic from your presentation(html)
meaning you can avoid the <% %> inline ASP tags more often.

for more info you really need to look at these sites


http://www.asp.net
http://www.gotdotnet.com