I have a strong preference for working in code, leverage IntelliSense and opening up all of the power of the C# language to work with WCF but I want to make sure that I'm not moving in a direction that ultimately will limit the WCF feature set I can access. My experience is so limited with WCF that I don't understand the benefits of using the configuration files, especially if you can do everything in code (?).
Note: I'm using .NET 3.5.
Can you do 'everything' with WCF programmatically or are configuration files required for the full WCF feature set?
You can do about 99.8% of things in code as well as config.
Some things can be done only in code - like setting user name and password on a call that requires those two for authentication.
And there appear to be a few things that can be done in config only - see this other recent SO question for one example.
But I think, if you prefer code, you should be fine for the vast majority of cases.
Marc