I use Vim and don't really need all the fancy code/whatever completion things, but how on earth do you get them? It seems complicated enough that I haven't bothered.
It's not to difficult, There are a ton of plugin's listed on the Vim site, and some on github. Most of them are just dropped into your .vim directory and some need to be set to startup in your .vimrc. Command-T(this one can acutally be kind of a pain to setup if your vim was not compiled with Ruby support), SuperTab, SnipMate are the three I recommend the most.
Thank you, I'll give them a shot now.
For something like on-the-fly highlighting of syntax errors it's usually just as easy as downloading the plugin and dropping it into your ~/.vim/ folder. For more some things you might have the extra step of having to remember a new command or keybinding, but that's about as complicated as it gets.
Emacs users should check out the flymake minor-mode.
ctrl-( p previous or n for Next) is built in auto-completion of what you are typing. It can be configured to use tags, files, only open buffers etc.
Ah, I do use that (rarely). I was looking for something more intelligent that might perhaps help with development, rather than with just typing.
You might want to look into Tags. They tend to be what gives vim its ide powers.