This post will show you how to change the change the default program or file association in osx that opens when you click on a file in osx (eg open gvim for .txt or open zend studio for php files)
right click on the file in finder
open the ‘open with’ section
pick the program from the list
click on ‘change all’
now every time you open that type of file in finder it will open with the program of your choice!