News via http://www.nintendomax.com/viewtopic.php?t=12618&f=54

Brawl Stage Studio is a PC stage builder for Nintendo's latest installment in the Smash series: Super Smash Brothers Brawl. It offers many new features not possible with Brawl's build-in Stage Builder like placing up to 252 blocks, loading custom stage preview images, having access to the beta block, placing spawn points and many more.

http://www.smashboards.com/showthread.php?t=217759