I’ve seen sales figures that say N-chan sells more merchandise than X-chan, but the Mixi ranking says that X-chan is more popular! What gives?
Keep in mind that just as there are many people who choose not to use Facebook, not everyone in Japan uses Mixi. Likewise, individuals may choose not to join communities on Mixi even though they are a fan of a band or individual. There is no single metric which is guaranteed to give an accurate picture of the overall popularity of a celebrity or group and these statistics are just one resource that fans can use.