I think the point the article is making is that Google has, in the past, made lots of "little" long-shot bets, (making up the $10+ billion/yr R&D you mention.)

I think the point the article is making is that Google has, in the past, made lots of "little" long-shot bets, (making up the $10+ billion/yr R&D you mention.) The Nest purchase is Google pushing a LOT of chips into consumer tech.