Remember that rumor a while back that digital download games for PlayStation Vita would be cheaper than retail, possibly by up to 40%? Well, that was bullshit. As it stands right now, in Japan at least, the prices for every game available in the PlayStation Store are exactly the same as the price for the retail versions of the games. While this could certainly change, or be different for different regions, that's how it stands here in the land of the rising sun.
So what's the benefit of the download versions? Well, nothing, other than not having to leave your house to buy it. You lose the physical box and card for the game (which have trade in or second hand sale value, plus collection value) and some people are saying the digital versions of the games actually have longer loading times as well. Not a whole lot of incentive there, although it is nice not to have to switch cards, or have to carry around a bunch of cards with you.
No official pricing has been released for other regions yet, so we'll have to see if North America and Europe follow suit.