The New York Times has an interesting article about Starbucks in which is discussed the company's foray into creating culture (not just the perfect brew).
Meanwhile, from here in Houston I've been debating how to label Starbucks. It's certainly true (as most would agree) that the experience here is not the equal of that in the Seattle area. So far I've come up with a few areas: ambience (environment, cleanliness), service (speed, friendliness), drink quality, etc. There are a number of subcategories to each. As a former barista I have the advantage of knowing what was looked for by "Snapshots" (the outsiders the company hires to rate service).
Soon I hope to start categorizing the service I get and, hopefully, become influential on the Houston Starbucks scene.