vim is good, so too is emacs. But I learnt the hard way why vim has one edge that emacs does not, size (I could be wrong anyone know of an emacs version thats <1Mb). If you know vim at command level you can pick up vi which allows you to edit all but the smallest systems that require tools like "ed" (installing openBSD http://goonmail.customer.netspace.net.au/2003OCT230736.html )
If you want to understand more about editors on Unix systems try reading "Raymond E., The Art of Unix Programming, Chapter 13, Complexity, A Tale of Five Editors" ~ http://www.faqs.org/docs/artu/ch13s02.html
vim is awesome. I discovered it after 8 years of Delphi, Eclipse and Visual Studio. After two months of a steep learning curve I could honestly say that indeed, vim alone can be as productive as any IDE.
If you want to understand more about editors on Unix systems try reading "Raymond E., The Art of Unix Programming, Chapter 13, Complexity, A Tale of Five Editors" ~ http://www.faqs.org/docs/artu/ch13s02.html