Kevin McCann, president of Novastrike's developer, Tiki Games, says the game is the first self-published title* available on the PSN. McCann rightfully points out that self-publishing might not mean much to gamers, but for small cash-strapped developers it makes PSN a nice option in the ever-increasing pool of digital distribution outlets. Not having to worry about delisting probably helps too.
*Everyday Shooter was self-developed, Sony published it.