A bunch of people asked for a demo of the completed project so here's a webplayer with a first person controller, wasd and space to move and left and right click to destroy/place blocks: http://naglestad.net/alex/
And here is a unitypackage of my project after the last part if you'd like to play around but I strongly recommend that you do the tutorial first. You won't understand the code without having done the tutorials and you won't be able to make much without an understanding of the project: http://www.mediafire.com/?o9nagnm0aa1d6lc