Lots of research already links sugar to obesity.
I'm not really sure why you feel it neccesary to laugh at me(at least that's how I took your post). Of course excess amounts of sugar cause obesity, but that doesn't make artificial sweeteners the answer. That's just not a logical argument. The real answer is to eat less sugary foods and more healthy foods. Sugar free jello, diet soda, etc are not healthy just because they don't have sugar - they're just have no calories. The new research is showing that most artificial sweeteners ar econsumed by people with weight issues (either current or past). Most people without weight issues drink regualr soda in moderation, eat healthy foods, have an occaisional sugary snack and don't obsess over the sugar in their food.
Also, keep in mind we are talking about children here. Not already heavy adults, not obese children, not you or me. children are still growing and their nutritional requirements are vastly different then an adults. Toddlers still need to drink whole milk - not low fat or skim, they don't need to worry about cholseterol and they don't need artificial sweeteners.
If you love them and think they are the best thing since sliced bread - good for you and feel free to consume them in copious quantities if you wish - you'll get no argument from me. Just don't tell other people that we should allow our children to consume there chemically altered sugar substitues and don't laugh when I point out that new research questions whether these artificial sweeteners really help in the battle against obesity.