The 16 year old age limit just seems silly. I was watching the men's 10m platform diving and the age requirement is 14. If China broke the rules, then it should be investigated. I just think the rule should also be changed. If you got what it takes to be an Olympian and win your event/sport then it should not matter your age. Good for you if you can handle all the training and pressure at age 12, 22, 32, 42 or whatever.
It does not surprise me that China won the most gold medals. The home team always seems to do well and China by far had the most participants. I think they had over a 100 more athletes participating in events than the next leading country, which I believe was the U.S.. The more that perform, the more chances to win medals.