I know of a 25 year old who got a 7-digit counter offer from Google when a friend tried to recruit him so I was hoping the 23 year old example wasn't too much hyperbole. Plus, the idea is to pay a big premium over what everyone else pays anyway.
That's insane though. It's hard to imagine a single programmer being worth a million dollars a year to a company.
AdWords is worth, round numbers because I'm lazy, $100 billion a year. One million dollars is 10^-5 times AdWords. Want to make a guesstimate as to how many engineers are associated with 10^-2 improvements in AdWords in a given year?