This is kind of awesome, and a compliment to the earlier article I shared, "Don't Call Yourself A Programmer." I like the author's introduction. It rings with me a bit and lots of others I know.
There's some great, no-bullshit tips for preparing yourself for a programming interview. Of course, the most important one is ABC; Always Be Coding. I couldn't agree more. Start a project, big or small. Finish it, or not. Start another one. Keep them on GitHub, BitBucket, SVN, running live, whatever. Do one in another language. In another framework. Make a game. Port something from another language. Re-invent something big and make it simpler, faster, and better (don't get too crazy -- depending on what you try to re-do, this is a mammoth). The point is, always be coding. Practice is practice, and you WILL learn.
Aside from that, the rest of the article is spot-on. Relax, be happy, practice pair-programming or programming in front of someone else, etc.