I agree with DonDare comments that the top earners listed in the post are made up of people most likely in the Internet marketing industry.
The truth is, the top earners of the Internet are definitely the online business giants like Yahoo, Google, MSN, Amazon etc. The reason is because they all have one thing in common that is they have a gigantic mailing list of individuals that use their free email addresses.
They make money by selling advertising space in the free email address inbox to online merchants, which runs into several hundreds of millions of dollars monthly.
Therefore, what is the mailing list population size of the individuals listed in the post to warrant being mentioned as "Top Earners of the Internet"?
You see, the larger the population of an Internet marketer's mailing list the more money he would make online.