Apple has already provided a few clues as to what it's going to put on the plate for developers at WWDC. One change that's unlikely to be touted at the keynote, or even the entire conference, could prove to be the most important for app writers: an alternative to the UDID (Unique Device Identifier) that Apple started phasing out a year ago. If Wall Street Journal tipsters are right, the hardware-specific ID will be replaced with tagging independent of any one iPad or iPhone, such
