Here are numbers that come from a study of a couple of thousand swedes, with
no reference to sexual preference that I could find. The point would seem to
be that (1) sexual activity follows a power curve, with a few people, a la
Wilt Chamberlain, having an extaordinarily large number of sexual contacts,
ev en in a short period of time and (2) a tendency for men to have more
partners than women.  I have no idea, being a statistical ignoramus, whether
the fact that there seem to be more men than women at the extremely
promiscuous end of the sex-partners-distribution curve means that you'd get
even more extreme results in a group of men who chiefly have sex with other
men.
http://polymer.bu.edu/~amaral/Sex_partners/Content_sex.html
<<For example, the mean number of partners since sexual initiation for women
is approximately 7 and in a sample of less than 1500 Swedish women we find an
individual with 100 partners. For men, the mean is approximately 15 and we
find an individual with 800 partners, which is almost 50 times larger than
the mean! So, somehow Don Juan was not such an extraordinary case but just
one data point in a wide spectrum of behaviors that can be observed. >>
As for gay men: There is indeed anecdotal evidence of cases of extreme
promiscuity among gay men. You can read about it in Randy Schiltz's And the
Band Played On. He writes about  bathhouse culture pre-HIV; he also discusses
how, in the gay politics of the time, there was a sub-culture of what you
might call radical gay men who argued (and acted on the argument) that having
many partners was an essential part of what being gay actually was. It was an
explicitly political statement: monogamy is an artifact of straight culture.
That view seems to have died, in more ways than one. Part of the point of
Schiltz's book was to condemn the role that it and  bathhouse culture played
in spreading the AIDs epidemic that eventually killed Schiltz, among so many
others. This doesn't let Eugen off the hook--but it is accurate to say that
there was a  cult of promiscuity that was particular to the gay community.
Tom