Yes, my wife is from a Polish family, and she loves ebony fingerboards!
Ugh, sorry, I couldn't resist.
I've never needed to oil or polish an ebony board, but have one that seems rather dry, so I'll be interested to hear some suggestions for improvement. I love deep dark ebony fingerboards, the best feeling wood there, IMO. I think I tried some Dunlop lemon oil once, but the ebony didn't seem to absorb it like rosewood does.
As an aside, I think it was on the Jeopardy TV show, I once heard the question:
Q: What's the only word in the English language whose meaning changes entirely by capitalizing the first letter?
A: polish
Dunno if that's true or not.