douglas bowman, creative director/visual design at google left a couple months ago b/c he was fed up with google's data driven decisions. basically he felt that there was little room for innovation, so he left... and now works at twitter.
it'll be interesting to see how douglas's perspective will affect twitter (in their quest to move to take over the real-time "search" universe).
read more the NYTimes article about this.
does your agency use data to help drive it's design rationale? i know mine does.