Linear progression works well for beginners and those who are starting proper weight training. The problem comes only then when you can't simply go forward with linear progression. I used linear progression for over half years, and the basic templates (Starting strength, Stronglifts) are based around it. Nonlinear(undulating, waving) progression has different intensities week-in week-out, and the template doesn't follow a straight, linear line (duh). You wont go from lower weight to higher weight step by step, or from higher volume to higher intensity. But you mix it up a little. 531 is pretty unlinear, since it has a deload microcycle, but the macrocycles are then again progressing linearry.
Peridodization is also good for some longer and larger goals that might need more than just one particular skill (i.e speed, strength, size or condition). I think the length of the blocks is determined by what you want to achieve: Where do you need the most work? Or is there a reason (Like a personal obstacle or focusing on some other skill) you need only maintenance? Also there are different methods, some like short training blocks and cycles, some like longer.
This is the most comprehensive (and not way too advanced) article I could find about the subject, describing different methods of periodization. If interested, go read it. But don't stress about this stuff. Just learn.http://articles.elitefts.com/training-a ... -training/
EDIT: Just to say this: Periodization is usually used when planning a year(more or less) of lifting, and it usually has several different abilities (like hyperthrophy, speed and strength) written in it, usually in blocks. When you are doing just one thing, you are not periodizating much. You can alter the progression of your hyperthrophy phase between linear and undulating, but there really is nothing more if you don't have anything else in your training plans. That is why I asked on what you want to include on your periodization. If you want, here are other great in-depth articles around the subject:http://articles.elitefts.com/training-a ... ion-bible/http://articles.elitefts.com/training-a ... -training/http://articles.elitefts.com/training-a ... odization/
EDIT2: As I was saying, these aren't necessary at this point of your training. You can, but you don't have to. Your quote from the link was from part "Intermediate to advanced training".