Strong evidence that Sony's Next Generation Portable would actually be called PS Vita emerged earlier this week. That's still unconfirmed, but Vita is now looking more likely, thanks to a new source: Sony itself.
After Sony launched an E3 2011 teaser page, nosy NeoGAF user gofreak dug through the source code of that page, seeing PS Vita listed alongside the company's other platforms, PlayStation 3, PSP, PlayStation 2 and PlayStation Network. None of those links are active, but the source of that page is still stuffed with HTML that points to a PS Vita.
A quick Google Search also shows PS Vita as a registered trademark of Sony's. It could still be a codename for the next PlayStation Portable—which already has a codename in NGP—but don't be surprised if Sony mentions those words at E3 next week (or sooner).
So. Vita? What do you think? I'm not attached to the existing three letter acronym, but I do love a good, contentious name for video game hardware.
Update: Sony has since removed mention of PS Vita from its source code, but here's a screen grab for posterity.
E3 Teaser [PlayStation.com]