There are, but as you might expect when a project like that gets started, even the smell of it attracts a lot of people. I can't say that anything I've seen at Google iterates quickly compared to where I've worked before. It's just not a company built for quick iteration -- between the code reviews and style guide and readability restrictions, a lot of discussion around design docs, interacting with a lot of other teams, etc.

But it has other strengths.