This happened to my best friend last night and pointed me to this link when he did some research. Just passing it along.
Originally posted by ArticleUnfortunately, gamers eager to sample the cel-shaded beat-'em-up were in for a very nasty surprise. That's because the demo contained a glitch that will erase all saved games on the memory card or cards currently inserted in the console.
they held a press conference this morning the short of it is * Still no evidence that PSN credit card data was obtained but cannot be ruled out * Sony to provide free selected software downloads in “Welcome Back” program.