For reliability and quantity of stores, Starbucks will always do a decent job on both espresso and coffee. Avoid the pushbutton machines if at all possible.
For great espresso, definitely go to Peet's if you can, or Torrefazione. Tully's has good espresso (not great), and coffee that should be avoided. If you're near a Seattle's Best Coffee, their coffee is good but their espresso should be avoided.
(Unfortunately SBC and Torrefazione have been bought by Starbucks. Argh!)
While I'm on a coffee rant, let me highly recommend Illy's espresso anywhere you can find it.
---Mark (former Seattlite)