I'm in the process of converting a lot of 1.8 style hashes into 1.9 style. This is frustratingly slow to do. Of course, not really because I have vim. If you find yourself in this situation, and have a file open with a lot of these in it of the form:

render :partial => 'foo', :locals => { :giggity => 'goo' }

You can just throw this handy regex into vim for maximum awesomeness (also, if you haven't used backreferences/capture in vim, note that I have to escape the parens):

%s/:\([a-zA-Z]*\) =>/\1:/g

That'll leave you with what you want:

render partial: 'foo', locals: { giggity: 'goo' }

Anyway, I am hopeful that Nick will rebound this post with one about doing the same thing project-wide using sed. Or someone else will generate a less-specific version, that handles string keys as well at least :)