My feeling on the announcement is more along the lines of what he seemed to let slip in the last Developer Live Stream. During the live feed (unsure if it's on the recorded version) he mistakenly mentioned Goblins as a playable race at one point. The other Dev's looked shocked when he said it if you watched their body language and expressions. When Cal himself realized he had said it he seemed to have a "damn I kinda let the cat out of the bag" look about him. He even turned to Mesanna and said "I did not just say Goblin did I?" When she said yes and started laughing he said he had meant Gargoyle.
I'm a strong believer that the Blue Wisp mystery is still active and yet to be solved. I've summoned it several times and tried handing it dozens of items(books, scrolls, runes etc...) and I'm now leaning towards the belief that you need to say something rather than give it something. Perhaps a series of trigger words that carry you through a conversation or a phrase of some kind, a phrase that you would assume to be written or said in game some where. My worst fear is that we will never be able to communicate with Wisps.
hmm...that text is directly ripped from the wisp you talk to in U6, if the "mystery" is the same the "source of knowledge" he wants is the book of mantras, which may be this termur quest book