Heres a link to a picture of the source code with PS Vita in:
http://cdn.medialib.computerandvideogames.com/screens/screenshot_255264.jpg
"Sifting through the source code for Sony's new E3 2011 website reveals mention of 'PS Vita' - the very name that's been much rumoured to be the final retail name for the PSP's powerful successor."
"The rumour mill has so far churned out supposed leaked pictures of what looks like an NGP leaflet or brochure, touting the 'Vita' name on both the page and the console itself, while others have dug up a domain name and a live development website with the word 'vita' in their URLs. "
"The evidence is mounting, and all will be revealed at 5pm PST on June 6. Although we remain greatly hopeful that it's just a placeholder. "
"Come on now... 'Vita'? Seriously? Every time we read the word we think of this person."
[Source]
http://www.computerandvideogames.com/304217/news/ps-vita-found-in-sony-e3-website-source-code/