Very recently (as of 4/21), all PSP games that are digital are now playable on the Vita, whereas before it was only a select few. However now that this is the case, many want to play Phantasy Star Portable 2 on the Vita, but as of a couple years ago, the game and it's demo have been removed from the PSN store and therefore the only people currently who can play it on the Vita is the people had had bought the game back when it initally launched.

The servers for the MP are still up and it wouldn't be surprising if the population got a bit of a boost from sales on PSN.

Please SEGA, bring back PSP2 to PSN!