The biggest PP change I've picked up on is improved entries. The old PP would do the deep drop, then have four guys standing at the blueline while one guy tries to carry it in, which only works reliably if you've got someone like Spezza to carry it. After failing at that a couple of times, the puck carrier would start dumping it in, but since everyone else is standing still, it was a possession loss almost every time.
Now, they try to have a couple of guys moving with the puck carrier, flanking him so he's got more options and it's harder to defend. Improved entries = improved o-zone possession time = improved success rate.