Just had to reply to this one! Generally ship the blades forward, like Cowboy and RichP (and others said), because you can keep your hands on or close to the handles. But sometimes you can just ship buy pulling them straight in. You haven't lived until you get your oar caught between a rock and drybox and it breaks off in your hand. You haven't lived until your double-tied up and the outside boat gets his oar stuck between two tree limbs. You haven't lived until you catch a downstream oar and it comes up under your armpit HARD. You haven't lived until your dory pitches and the upstream oar catches a rock and snaps free, breaking your right arm (spiral fracture of the humerus) at the top of Big Drop 3.
It's good to think about oars and what to do with them. They can be the most dangerous thing on a boat.