Looks interesting, in spite of those scary heads.
The Sony PlayStation Suite is now in “Open Beta”. This means that you can download the SDK and start writing games and applications which you might eventually sell via the PlayStation Store. The way I see it (although I’ve not tried yet) you should also be able to get programs running on your own PS Vita using this kit and the PlayStation Suite Development Assistant. The path to market looks like it will be very similar to the App Store or Windows Phone Marketplace, with developers paying an annual retainer (the traditional 99 dollars) to allow them to unlock devices for testing and to sell their wares.
The good news is that the development language is C# and the way that it all works is not a million miles away from XNA. In fact it works so well that we had quite a few teams in our Three Thing Game end up making games using it.