If there is a truly "West Coast" brew, then it has to be the Pale Ale. Microbrews from Seattle to San Diego vary widely in the beers they offer, but I can't think of a single brewery with any reputation that doesn't have its own version of the medium-bodied hoppy ale. And of course the most widely available West Coast brew is Sierra Nevada's Pale Ale. (It's the only West Coast beer that appears with any frequency on the East Coast.)
From Bend, Oregon, the Deschutes Brewing Company sends its take of this brew. The Mirror Pond Pale ale is a bit drier than Sierra Nevada, but despite this it maintains a full flavor. However, what makes the Mirror Pond distinct is a subtle tartness which may be masked if the beer is consumed with especially flavorful food. Thus, the beer is probably best appreciated before diving into a hearty meal. When consumed along with a burger or a burrito, the fainter flavors fade and it tastes like "just another Pale." Of course, this is not necessarily a problem for those of us that love our Pales.
All in all, I think Mirror Pond is probably a step ahead of the vast majority of American Pales. It's also a fairly widely available alternative for those who are a little bit tired of Sierra Nevada. But the search for the perfect Pale must go on.