I know lots of people who have done it fine, but babies have all been taking pureed food and supplements of bottles or water.
Personally, I won't be fasting this time. I did it when DD was 11 months and in hindsight I really wish I hadn't. She was very slow to take to solids and she lost weight while I was fasting, which led to her being given special formula. To this day I can't understand how I was so thick as to not realise that she needed the breastmilk to keep her going. I think I was just a naive first time mother and thought that food was more important at that stage than breastmilk, which is completely not the case.
I think that there is a dispensation from fasting for breastfeeding mothers for a reason, and that it is telling that the exemption is based on the mother's evaluation of the risks to her child's health and wellbeing and not anyone else's.
Kellymom has some more fact based information on fasting and breastfeeding here. The consensus seems to be that it is fine as long as you are drinking lots and they means LOTS at night, and it has more implications for maternal health than for the child, but I personally don't feel the need to risk it, and don't appreciate it when others pressure women into fasting on the grounds of "we all did it and it was fine".