As someone who has played since Vanilla, and raided pretty hardcore from Vanilla through to Cata. I killed I think 3? at most Normal mode Raid bosses in MoP.
Considering these stats are also only on accounts active in the past 30 days, where a lot of people are still away from MoP waiting for WoD to drop, 1M/7M is actually quite a large number.
It surprises me people are so surprised by this.