I woke up the next morning at 8:30 AM and checked it; it was still running. I put on my headphones and headed to class with it and let it run all during my classes throughout the day. I had a nap, ate two meals before 9:45 PM and started my homework at 9:00 PM Thursday night. 23 hours and counting. I did my homework, watched Pirates of the Caribbean: Dead Man's Chest and had a bedtime snack. I dosed off with my headphones and woke up at 4:10 AM and it was STILL GOING! Since I needed if for the next day, stopped it at 4:15 AM a decided to call it good there.
Estimated battery life of my Zune 120GB: > 30.5 hours or 30+ hours. INSANE! It preforms better than the official time given by Microsoft and there was no telling how much longer it could have gone before it would have finally died. Needless to say, I'm very impressed. Good job, Microsoft!