OSX Knows Better Than You: How to change the default application for a file

In case it wasn’t obvious by the number of Apple related posts as of late, I’ve been spending almost all my time on OSX based machines. One of the things I’ve found annoying is that I couldn’t change the default file/application association, or at least I couldn’t figure it out. I watched a lot of (downloaded) videos on my computer and every single time I do so, I have to...