My daughter was the same way. She will be 11 months old in a few days and she just started self feeding in the past few weeks. She just did it out of nowhere but before she was doing the same as your son.
As far as not holding his cup, my oldest wouldn't do it himself. I swear he was 15 months old before he ever held a sippy cup or bottle. He was spoiled though being my firs child, I did everything for him. Why would he want to hold his cup when he knew I would do it for him? So, I stopped and he had no choice. I learned from him, with my daughter I had her holding her own bottle at 7 months.