Little else is known about the Vita version of the game, like release date or price. When the game moved to PS3, it added additional content not found in the Xbox 360 original. However, we'd fathom that cross-play and cross-buy features won't be included, given the port will come nearly two years after the original PlayStation Network release. (But, we can hope, of course.)
Update: Playdead told us that no additional content is being added for the Vita version and that cross-play features will not be supported. However, they did mention something of a PlayStation Plus promotion...
Andrew Yoon posted a new article, Limbo creeps onto PS Vita.
Playdead's critically acclaimed child death simulator Limbo is coming to PS Vita.
I like that game but your description of it still made me chuckle.