Keynote I guess pushed an update that doesn't take hightlighted code from xCode anymore. So, I googled around and found hightlight. It is a super useful utitlity to do syntax highlighting from the command line.
$ brew install hightlight
If you are on Mavericks you may need to
brew link lua to get it working right.
Hightlight has support for all kinds of languages and themes and it can wrap the code with line numbers, which is great.