[orlp]

If it were just solely :) / :( then it is a freshman's exercise in expectiminimax.

[pvillano]

it turns out you don't need anything more than minimax for the general case Here's my solution https://github.com/pvillano/probabalistic-tic-tac-toe

[orlp]

I think this fails to take into account that your opponent can also roll 'meh', making it your turn again.