Sony has properly introduced the “Cross-Controller” feature for PS3, with the announcement of the Cross-Controller Pack for LittleBigPlanet 2. Cross-Controller play allows you to use a PlayStation Vita instead of a regular DualShock 3 controller, and while that does mean you're restricted to only the one shoulder button on each side, you can also use the Vita-specific features like the front and rear touch.
Better yet, you might also find yourself switching to the screen on your Vita for some of the game before moving back to your main screen again. Looks like the Wii U is not so unique in that respect after all.
As far as LittleBigPlanet 2 is concerned, this Cross-Controller Pack brings a whole new adventure in which “Sackboy joins up with a group of lovable Space Pirates as they race to find a valuable treasure long thought lost to the Cosmos.” The new levels will contain obstacles that can only be surpassed by using Cross-Controller play, i.e. making use of the Vita's touch functionality etc., and players will also be able to use new tools to implement these kinds of obstacles in levels they create.
Since it looks like players won't be able to complete this add-on without a Vita, I really hope the Pack comes with a warning when it appears on the PlayStation Store next Tuesday (December 18th).