I'm a begginer and I'm using 4.2 LTS for production reasons.
The usual Blender version disclaimer. If you want to follow along step by step, it's better if you use the same Blender version as the teacher in the video. That way you can follow exactly with what's on screen. The version of Blender is of little to no consequence, Kent gives the best explanations in this short thread:
https://cgcookie.com/community/19346-not-sure-where-to-start-learning-blender-begin-here
Thanks for the replies, I realize now that I missed the creation of the array object empty, and of course blender won't let me use the modifiers on the cube as an array object, definitely my bad. Regardless good to know where I can see the version so thanks again.