the point made was that fruit juices will make you fat just as easily as sodas.
the problem is that juices contain all the sugar from fruits but without the fiber (and some of the beneficial phytochemicals are also lost). in fact, many juice products are concentrated (essentially dehydrated and only partially rehydrated), so they are actually more calorie dense than fresh-squeezed juice.
so, if you count all your calories and the total you consume is constant as per plan, juice won't make you any more or less fat, but neither will soda.
so why don't i drink juice?
1) i get less nutritional value from it for the same calories as, say, a piece whole fruit and a glass of water.
2) the other issue, especially for the masses that aren't explicitly counting calories, is that the calories consumed in liquids do not effectively trigger satiety the same as solid foods. therefore there is a tendency to consume higher total calories. (not surprisingly, semi-solid foods (i.e. soup) trigger satiety better than liquid calories and less than solid foods.)
-bug