Model 1 (M1) is the procedure from last year and is based on normal averaging. So far, this has been the most accurate model. M2 is based on moving averages, and M3 is based on weighted percentages (thereby allowing games later in the season to count more than earlier games.) AVE is, of course, the average of the three.
The Power Ratings are based on the summation of M1, M2 and M3. The ranking looks pretty intuitive to me.