I believe they specify that they only count singles/albums/DVDs.
http://ahsforum.com/forum/showthread...=oricon+yearly
Dang, she was #2 in 2008 with 7.1 billion yen. I guess A COMPLETE really helped, and the lack of competition from GReeeeN and such. Did B'z get helped this year by Ichibu to Zenbu or what!?