Well, this is starting to get confusing. First we got a report that users would be limited to only one PlayStation Network ID per PlayStation Vita, and then Sony told Wired that you could have multiple PSN IDs, you just needed to store them on separate memory cards.
Apparently, the first report was right all along; a Sony rep told Wired today that you are, in fact, locked to only one PSN ID account per PlayStation Vita. If you were to want to switch to a new one, you’ll have to reset the hardware to its factory settings.
When Sony issued its “correction” to Wired earlier this month, it said that PlayStation Network IDs would be tied to your memory cards, meaning that you could have multiple PSN IDs if you also had multiple memory cards. Sony’s latest correction, on the other hand, says that PSN IDs are tied to your Vita and your memory card, meaning no multiple PSN IDs.
“[The] PSN account is tied to the hardware and the memory card, not just the card,” a Sony representative told Wired in an e-mail, “which means that if a second person is using your Vita, it’s not just a case of switching out memory cards, it’s clearing out all of your saved data on the Vita itself when you do the factory reset.”
So, there you have it; you can’t have multiple PSN IDs on your PlayStation Vita. Unless Sony changes their mind again, that is.