In an interesting piece of news, it has been revealed that the PS Vita and PSP can play ad hoc compatible games together. Ad hoc is used to play PSP games with other people nearby using it’s Wi-Fi signal. This might not seem that exciting but with ad hoc Party on the PS3, you can play ad hoc PSP games with anyone else on the service. This basically makes it an online game but removes the portability of the system.
The PS Vita can download PSP games from the PlayStation store meaning that you can still play Monster Hunter with your friends from back home on your Vita or in person if you want to ad hoc more traditionally.
Source: Siliconera