While this is a sad situation, I can't really find too much fault with arrest. They guy stated that the burgler was at his neighbors. Had he been coming toward him, threatening him, etc., I could see him defending himself, but his quote (granted the press is rarely correct) made it sound like self-defense was an after thought.
If you aren't going to shoot the guy to protect yourself, don't draw the gun. Call the police, give a great description to 911 while watching the actions, and be ready to defend yourself. However, shooting into the ground would get you arrested here, too.