A look at the source code on Sony's E3 website provides new evidence the finalized name for NGP is a complete departure from the original PSP branding, Vita.
Within the code, there are several references to "PS Vita," which matches the name featured on images from earlier this week.
Kudos to gofreak on the NeoGAF message board for discovering this hidden gem.
I'd previously confirmed with multiple development sources Vita was the working codename for PSP's successor, with NGP a temporary stopgap. Sony had been internally unable to come to a consensus on a new name, but today's evidence points strongly towards Vita making the cut.
Who wants some bottled water?