I spent an hour reading about TextMate to get a feel for what I'm missing since I know it's so popular. I'm sure it's a lovely editor, but I have such an emotional attachment to Vim, Linux, free software, etc. Anyway, I'm sure you're tired of hearing me talk about that ;)
Anyway, I tried out the snippetsEmu plugin. It's a plugin that provides TextMate style snippets. Once you have it installed, you can edit a Python file, type "def<tab>" and it'll start doing interesting things.
I can see the appeal of snippetsEmu for more verbose languages. It knows how to type "public static void main" ;) However, it's hard to get excited about it in Python. Python has such low syntactic overhead that it's faster for me to just type things out, especially considering I'm a touch typist. It'd probably make more sense in Ruby, where you have to type "end" all the time. Nonetheless, I'm happy to have someone tell me how to use snippetsEmu more effectively.
I also tried out xmledit. That one's a keeper. Once you have it installed, you can type "<p><tab>" and it'll automatically add "</p>". Hit ">" again, and it'll even put the two tags on separate lines and position your cursor between them. Very nice! The one trick to remember though, is that when you install xml.vim into your ~/.vim/ftplugin directory, remember to symlink it to html.vim so it works for HTML too.