If any of you want to get a good idea of strike zone accuracy by MLU's you can watch the Gameday application. Most parks are now running the PITCHf/x tracking system which displays the path, trajectory, release speed, result speed, amount of break, and position in the strike zone for every pitch during a game. It is accurate to within a half-inch and often much less. Most pitches that I track are accurate to within 2/10's of an inch. You can also go back and replay a pitch sequence from any at-bat. Here's a screenshot I just took during the Cubs game:
