I've been tasked with writing a feature about code editors.
This is not a "vi" versus "emacs" piece. The idea behind the
piece is to describe when to use code editors versus when to
use IDEs.
I typically use whatever editor fits in best with the rest of the build tools I'm forced to use. I use ProjectBuilder a lot. At the moment I'm using IntelliJ IDEA because PB's java debugger is broken for non-trivial projects.
I'm just as likely to use vi - most important feature is ease of initial invocation followed by ease of fixing indenting, ease of jumping to a line number, ease of finding/replacing text in multiple files. Otherwise I could care less about the rest of it.