If I were in his shoes, I'd do another startup. Why would you become a corporate bitch again, after you tasted the freedom of doing your own thing?
It is an interesting opportunity, so I'm trying it on for size.
Interestingly, Google was both least aggressive and least attractive to Schachter. When he'd interviewed for a job there, the company had told him, "We don't need idea guys--we've got plenty of them. We just need developers." Now Google was wracked by internal debate over the value of Del.icio.us. Schachter says, "They came in and said, 'Well, maybe we're kinda sorta interested,' but there was no 'What's the plan? What are you thinking about? Where do you want to take this?'"