Cupertino "downtown" is a joke (I used to work there)... it's basically the intersection of two large streets (Stevens Creek at De Anza).

Likewise Sunnyvale and Santa Clara are quite anemic, but Los Gatos, Saratoga and even Los Altos aren't bad. MV and PA are great places to dine.

Cupertino is the only town I've worked in that never had a downtown.