These days, the nailing down of deck boards is much less common. People are spending their hard earned money on quality kiln dried hardwod deck boards and want better fixing than just nails.
Deck Screws are becoming the prefered method to securing deck boards as they generally pull down tighter, they have greater long term holding power, the heads don't pop up like deck nails, there's no hammer impact against 'anti-corrosive' protective coatings and they come in a huge range of sizes to suit many different types of decking applications.