Did anyone bother to go to the links that this was supposedly sourced from? Because I can't seem to find a valid source. I tried both the addresses that are in the first post and neither are valid.
Several things struck me as odd about this list, beyond Ayu's ranking. For example, SMAP being ranked higher than Koda Kumi even though they only released one thing this year so far. When you look at the oricon numbers, there are a number of instances that don't quite make sense. If someone can actually find the real source that this came from, please post it...
Otherwise, its better to just wait until real official numbers come out from Japan at the end of the year.