I too think this cannot be true. If Google had 1 hit in his first month, and traffic doubled every month for the 5 years he was there, Google would have had 576,460,752,303,423,000 hits in his last month.

For illustration, if google had a single hit in the first month of 1999:

  monthly traffic 5 years later = 2^59 hits

Which is the equivalent of every person in the world using google 83 million times that month.

Perhaps it was meant to say "every single year"? Since I agree that a 2x increase per month would be next to impossible.

Per year would see a 2^5 = 32-fold increase from '99-'04 though, which would seem plausible.

So I'm going for this line being a typo, with year not month being meant.

I left a comment asking for him to reiterate on that part, let's see what he says.