There's something more basic about the analogy I object to. Google, Friendster, Altavista and Facebook were not founded at the beginning of a singularity.

What do you mean by that? You think Google isn't going to go on to develop machine intelligence? Surely they are among the front runners - though admittedly there are some other players in the game. This is not a case of hanging around for some future event.

• The first creatures to develop human-level intelligence came to dominate all other creatures.
• The first humans to develop agriculture did not come to dominate all other humans

The wording of the question was:

Compared to the farming and industrial revolutions, intelligence explosion first-movers will quickly control a much larger fraction of their new world.

It doesn't say the control is kept indefinitely. So - for instance - Sergey and Larry might die - but they will still have quickly come to control a larger fraction of the world than any farmer or industrialist.