Chris Penner is just starting out with Vim, and he's written an interesting article about his experiences: Vim Vs. Emacs?. I remember being in the same position, and the reason I stuck with Vim was the reason I could have stuck with Emacs: I didn't want to waste time learning a platform-specific editor. Also, Emacs and Vim work well in the command-line, which is great if you're an old school server-loving IRC nerd like me.
One of the beautiful things about creating vim commands or mappings is that it uses the same interface as normal editing. The mapping you need is exactly what you'd type inside the editor. This means that the more you learn in the main editor, the more customization options you unlock.
Emacs is also great (and far ahead of Vim) when it comes to doing more than one thing at once, and for being able to run and check code as you work on it.
When you're just getting into programming, deciding on an editor is a difficult decision. If you follow all the popular blogs with screencasts you have enough to worry about, never mind how to use a complex tool like a text editor. Which is why you'll find people using whatever the popular tutorial sites use. If a famous programmer uses Vim, then a generation of developers will switch to Vim.
The post also has some good comments from people who use Emacs or Vim full time:
I've been using VIM previously for many years but for some reason never really got into it deep enough to see the benefit compared to something like Sublime or TextMate. But once these other tools seemed to have neared their EOL I switched back to VIM and this time I wanted to get it right...
This was posted by "zerok", and I seem to remember a whole load of people switching from TextMate to Vim. I still haven't seen that many people using TextMate2, despite it being open source and actually pretty interesting.
So, Vim or Emacs? I don't know, pick one and stick with it, or learn both if you've got the time!