Microsoft have anounced that c# is going to have Edit and Continue support - a long wanted feature for vb.net'ers who lost the feature after VB6, and will gain it again in Whidbey.

http://blogs.msdn.com/somasegar/archive/2004/10/15/242853.aspx

I have heard some people state things along the lines of "real programmers don't need edit and continue" - these sort of arguments about "real programmers" I am always suspicious of, and in this case I think the argument is pretty slim.  Sure if you are doing Test Driven Development, then you reduce the need to debug, but you don't eliminate it completely, and E&C is another tool available to you to help you on your way.  It has been argued that E&C leads to poor unstructured code, because you are making adhoc changes that may be hard to understand, but I think that E&C has nothing to do with that, poor code is poor code no matter how you got to it, and that is a reflection on the programmer skills not the tools he or she used. 

Why would you not want it?  E&C is a tool in you toolset - use it wisely and you will find benefit.