This isn’t really an update that fixes the issues with the vita, but more of a work around. The latest update available is still the one we spoke about last time. It includes the following changes:
– tempGBA now correctly saves sram to the correct folder (.sav extension)
– fixed an issue with tempGBA when loading compressed archives.
– pce-fast: fixed most graphical glitches and improved speed a lot. most CD-rom games now run close to fullspeed.
Recently retorarch’s developer aliaspider had posted in their forums saying:
rename a core .PBP to EBOOT.PBP and put it in its own homebrew directory ( or replace the one in the main retroarch folder ).
This workaround has been now confirmed working on a PS vita running TN-V. Thanks to member SILENT_Paul, who posted a video demonstrating it running on a PS Vita, on retroarch’s forums.
Vita users now’s your time to go ahead and give this a shot . 
If you encounter any issues, feel free to address them into retroarch’s forums. I’m sure the developers will look into it once you’ve done it appropriately (giving as much information as possible of course). Remember due to the lack of extra ram on the Vita’s eCFW, you’ll have to use the PSP 1000 version. Anyways happy emulating!