Actually, we care deeply about customer feedback and several of us on the product team read the threads on the product forums personally, especially when there is vocal feedback. We don't necessarily act on everything, of course. With a product that operates at global scale we have a huge responsibility to make sure we are making optimizations that improve Gmail for as many users as possible, and the only way to do that is to rely on metrics and surveys that capture the entire user base. Otherwise we would be, by definition, changing a UI used by hundreds of millions in response to a vocal, non-representative minority. Basically we use the product forums and social media to figure out of there are trends or issues that we should be concerned about, but then always validate those issues with real data before taking action.