I can offer this article explaining the anti aspartame side of things
http://www.mercola.com/article/aspartame/dangers.htm
Someone can perhaps find a pro aspartame article so we can compare the two sides of the issue. Like Talesin I tend to mistrust the big food and pharmaceutical companies.
Once upon a time Flora advertised their trans fats laden margarine as good for the heart, made with natural plant oils, no artery clogging animal fats. Only they were no longer natural after having gone through the margarine making process.