I just checked this out and the Region appears to be set at A/1 which is US, not Region-Free. Did anyone else find something different?Amazon.com are selling the three series bundle for $59.99, which as it's Region Free is fine for me.
Amazon's listings are usually suspect, they just stick the region of the country of origin on. Blu-ray.com is the place to look for Region coding info.
http://www.blu-ray.com/movies/Star-Trek-The-Original-Series-Three-Season-Pack-Blu-ray/7193/
http://www.blu-ray.com/movies/Star-Trek-The-Original-Series-Season-1-Blu-ray/4189/
http://www.blu-ray.com/movies/Star-Trek-The-Original-Series-Season-2-Blu-ray/6281/
http://www.blu-ray.com/movies/Star-Trek-The-Original-Series-Season-3-Blu-ray/7192/