Blizzard has just updated Diablo III with Patch 1.0.3.
The list of changes is extensive, so we'd advise you head here for a comprehensive explanation of the tweaks and changes made by Blizzard.
One major change that was seemingly slipped in with the update was Blizzard's decision to lock new users to the Standard Edition (the demo version) for up to three days after purchase. A move that could infuriate gamers trying to get stuck into their adventure in Sanctuary.
Blizzard explained it best: "Digital purchases do require a review period before they kick over from Starter to Full editions. We apologize for the inconvenience, but it is a necessary step to combat fraud and other malicious activities that can weaken everyone's play experience. The delay is no longer than three days, and is often much quicker than that. Hang tight."
Until the account is switched over to the Full Edition you will only be able to play Act 1 up to the Skeleton King, there'll be a cap at level 13, matchmaking will be with other Starter Editions only, there are no auction houses and Global Play is not available. Blizzard also warned that anyone attempting to connect their Starter Edition in a region other than their Battle.net home region will be faced with the dreaded Error 12 (we're not sure why it's scary, but it is).