Yeah, just download via the PSN store.
I think it's better if they could also sell prepaid cards especially for those who don't own a credit card.
That'd be awesome and sooner or later Datablitz or any retail outlets would sell them.
By the way, there's a recent study rather survey that 'maybe' the PSN would opt for a rental store too.
That's also cool, if the price is right. You know what I mean. Well, let's just wait and see.