I was asked the question above by a few of my customers.

Usually the question goes like this: "So why do I need a software architect? I have a .NET guru with quintillion years experience, who knows the internals of every class library you can imagine."

I won't lay the long answer here, but the short one is very simple:

".NET guru knows what can be done in .NET. Software architect knows what should be done in .NET".

What do you think of it?