On April 21st Sony caused a stir when it appeared that PSP and PSOne games would be available for downloading and playing on PSVita. While this was indeed true, it was temporary and soon redacted. It is more than likely that such a change was accidental: a very unfortunate outcome as this would make the Vita an exciting purchase. This would have given people an additional means of playing games such as Valkyria Chronicles II on the PSVita. Even Shu Yoshida seemed to be fine with the development as he talked about playing the first Spyro the Dragon game.
However, this brings attention to the fact that Phantasy Star Portable 2, the last Phantasy Star game to be localized for release in the West (since the expansion game Phantasy Star Portable 2 Infinity was not released outside of Japan,) remains de-listed on PSN. This has been the case since at least January of 2012. When the ability to download PSP and PSOne games was available, Phantasy Star Portable 2 was an option for download, though only for those who had already downloaded the game before.
Credit to Siliconera for the image.