Hmm probably not feature wise. This was hacked together on the train. One advantage though is sharing code quickly (no download or reg) in any browser.
Etherpad is optimized for text, while Ace (the editing widget CodeShare.io uses) is built for code. It has syntax highlighting, folding, automatic indentation, etc.
It looks like Etherpad Lite may be using Ace, but I don't immediately see a way to turn on the nice programmer-y features.