The number one advantage smartphones have over any other camera is a development platform. Need a self timer? Done. Want to give your photos a vintage analog look? There's a slew of apps for that (My current faves are Camera Bag and Hipstamatic for the iPhone). Image editors let you crop, rotate, manipulate and tweak your images to get the most out of them. No other digital camera has this level of control without the aid of a computer. Jumping in blind is overwhelming, so be sure to pay attention to star ratings and comments.
Below, you'll see a pretty marginal photo taken with the default camera app on an iPhone 3G. Churning it through Camera Bag helps eliminate some of the distraction while giving a pretty compelling vintage look that fits with the car. LINK