Because they are lovely

First of all, they both have great smiles and just look happy, which made me happy.  Also, the woman's outfit has amazing proportions and is just so perfectly balanced and coordinated without being too matchy.  The man plays it cool with a simple t-shirt and jeans combo, but keeps it interesting with the wide-neck of the shirt, the 'not your average baseball cap' hat and those substantial boots.  They both look hip and it is apparent they put thought into their sartorial choices, but are obviously not fashion victims.

Photo Credit: The Sartorialist