I wonder if the olive wood reports are coming from the places (like Spain or Italy) where it's easy to get fresh olive wood...

The anecdotes don't seem to specify that it must be fresh, no. Consider gjm's anecdote right here: I doubt a chess board made of olive wood is all that fresh when it's bought by the end-consumer, and if the freshness made a big difference and the chessboard was just months old, then the effect should've noticeably gone away. (That wood lasts a long time makes sense - the oils and other chemicals must be able to take a long time to leach out in at least some cases, because otherwise, there would be little point to things like cedar-lined closets.)

I buy olio nuovo here and can attest that it's very different from the supermarket olive oil.

Mm. I was kind of hoping for an Amazon link, since I need to do an order on there soon anyway for Christmas gifts.