Sony announced on October 9th the Adhoc Party for PSP service. The beta version of Adhoc Party would have launched on October 30th. Today Sony Japan said that the service will be delayed till some time at the beginning of November. Update: PSP Adhoc Party launched.
Adhoc Party for PSP will allow users to play PSP software titles featuring ad hoc mode over the internet through Sony PS3.
The beta version of adhoc Party for PSP will become available through PlayStation Store, free of charge.

By downloading and storing adhoc Party for PSP beta version to the Sony PS3 users will be able to play PSP software titles supporting ad hoc mode such as Monster Hunter Portable 2nd G from Capcom Co., Ltd and Phantasy Star Portable from Sega.
Via the Playstation site (Japanese).