Ok, confession, I am a bit out of date on wolverine comics having not read any between 1997 and 2013! Anyway I got a copy of Wolverine, "Inside the world of the Living Weapon" yesterday and its a great reference book for all things Wolverine. It was written in 2009 and says Wolverine's healing factor is not what it was and he could die. Could someone please explain what happened and whether his healing factor came back to its old level. Cheers.

Which was clearly overlooked by most writers. He's pulled some powerful healing feats since 2009.