It is not an easy drive by location but definitely worth a dedicated visit. It is located amongst a cluster of high end shops and restaurants that are all independent in nature. Right next door to Portola is a Seventh Tea Bar that serves siphon/clover like teas.
Portola is hip, calm and refreshing. The staff are in while lab coats and are friendly coffee geeks. Their Slayer is due to go away to be replaces by a Kees van der Westen Spirit.
The coffee and atmosphere is already worth the trip, but what really tops it off and makes it compelling for me is the Crispy Almond Croissant, and their other savory breakfast items.
The coffee is roasted a bit more dark and European in profile. This applied to the single origin and their standard espresso drinks. This I am comparing to the other third wave roasters, and not saying it is at all like a traditional roast.
All in all if you are in Orange County, this is a sure place to have to visit.