I think you have a point with the moving target, but also I believe that development should pretty much always be a moving target. You should be refactoring your domain based on new experiences and new knowledge all the time. So, personally, I find integration tests much more useful, because they test the input and output of a system, rather than how it's implemented. I can change my domain without having to modify my tests and that makes changes to the domain much simpler.

That being said, I also definitely recognize the advantages of TDD, I just don't think it's a silver bullet; there's good projects for it and bad ones