I'm more reluctant to trash Kurzweil, but this image hiring policy is taking on the look of some sort of bizarre Victorian menagerie where they keep old famous computer scientists in wrought iron cages for Googlers' amusement. It's like the Henry Ford museum, but they're collecting people. That's more than a little weird.
It could be argued that such things happen in academics too.
But this is not the same, famed people established themselves at Microsoft and AT&T. There wasn't this sort of hiring of celebrity. Someone of Kurzweil's stature could be doing his own research and simply hired on as a board member.
There are plenty of widely known people at Google, but seemingly in spite of Google rather than because of. Maybe that's a consequence of 20% time too. But if people's reputations are staked in things other than the company, the company seems to borrow more reputation than it makes.