Debuggers, autocompletion, even syntax highlighting help a great deal. I like to think that they let you program on a higher level.
I usually program in Emacs, but fire up an IDE when I need to debug or want some assistance in navigating the codebase or learning some new library.
I find that the code I write in Emacs is much more succint and cleaner. I think the more layers you remove, the more you can focus. I bet that if I wrote my programs with pen and paper, my programs would be much more beautiful.
But if you need to manage complexity, it is far more feasible to use an IDE.
Choose the right tools for the job. Use editors/pen and paper/whiteboards/IDEs to meet your requirements.
Advocating the use of text editors over IDEs is IMHO the typical example of the "Real programmers use Fortran" syndrome.
