Recently, PlayStation rolled out the new 1.65 firmware update for PS Vita, which added a couple of small changes to the older firmware. But that is not all, it also had two major effects; one of those effects being the loss of VHBL support, at least for Motorstorm Arctic Edge, and Everybody's Tennis. The other majoy effect that firmware had, was it caused the system to lose the ability to use adhoc play on PSP titles.
Apparently, they have released the 1.66 firmware update, which restores the lost adhoc play feature. Also, it appears you can use SKFU's Vita Pr0xy tool to spoof your PS Vita's system firmware version, which will allow you to access the PSN store. He is a quote from Wololo with more details.Source
