Yesterday we reported about it, today Blizzard has released a hotfix for the Immortal Wizard Exploit that was unveiled yesterday. All players had to do was Select Teleport - Fracture (rune), Select Archon - Arcane Destruction (rune), Hover their mouse over their character and Press Teleport and quickly after press Archon. That combination triggered the exploit and the Wizard characters could not be killed, regardless of the game's difficulty. So there you have it everyone, no more immortal Wizards for you :-P
We are currently rolling out a hotfix for a recent bug regarding invulnerable Wizards. We will continue to carefully monitor this issue and welcome anyone with information about bugs or hacks to submit a detailed report to our Hacks Team by emailing hacks@blizzard.com, or by completing the Hacks Report web form. In your correspondence, please include any steps necessary to replicate the issue as well as any additional details you are able to provide.