Recently it was discussed as to why Sony does not make something akin to Super Smash Bros. on the Playstation 3. This got me thinking, as to why Sony does not utilise their IP in more cross overs. Little Big Planet is a great start, but if Sony wants to establish a strong fanbase for their characters, they need to utilise them more in AAA games. This method of "exploitation" of IP has worked wonders for Nintendo who have successfully incorportated their characters into a number of games. Thus successfully making them gain mass appeal and recognition in addition to building a strong core fanbase of consumers which buy their games in droves.
As this generation has proven, you cannot rely on third party developers to carry your console forward. This is because their interests do not always neccessarily coincide with the interests of your platform. For these reasons, Sony has invested heavily in their first and second party development. Using the above method, Sony will effectively strengthen their core IP's which means they can be less reliant on third parties in the future to drive sales for their console.
The reason why Sony should use the "Little Big" moniker for these cross over games is because it is a unique and charming title which is unique to the Playstation brand. Not to mention, Sackboy has the potential to be one of the most marketable mascots out there. Sackboy appeals to people of all ages, gender and the ability to alter his appearance makes him all the more suitable for these types of games. Not to mention LBP and Sackboy have become a somewhat established brand with estimated sales of close to 2M units sold worldwide for LBP.
LittleBigBrawl: This could be a super smash bros. type beat 'em up involving recognisable and new characters from all of Sony's IP (and maybe even a few 3rd party characters like Snake and Sephiroph).
LittleBigRacers: This is basically modnation racers, but with sackboys + recognisable Sony characters from the get go (not DLC, since we are trying to promote these characters).
So in short, make this happen Sony!