On 6th Nov 2014 Blizzard wiped archeology history for a number of players, primarily in EU, but also US. There are some blue posts in the EU thread http://eu.battle.net/wow/en/forum/topic/12618122585. Two months later the problem is not fixed and it looks like Blizzard is just waiting for it to go away.
I was surprised to discover this problem myself only when I started to do Draenor archeology. Even though I read mmo champion (and other wow news sites) daily this problem was never mentioned before. I consider progression data extremely sensitive in any RPG game, so I'm not going to let his go away so easily for Blizzard.
First let's see how many chars were affected, please fill in this google form with your affected character http://goo.gl/forms/v7ZDDtSzp8.
Once we have a list of a significant number of affected characters let's convince any/all major wow news sites to cover the story.