American Airlines called me and said they're not flying to Houston this weekend, and would I like a refund? (This sort of thing is why I love American.) So, no Cubs game after all. I just hope Houston is still there when I continue the 30-Park Geas next season:
Update, 22:00 CDT: MLB.com has the story, including the back-story, about the league cancelling Friday's and Saturday's games.