Well, the gall bladder's primary function is to screen out grease (in simplified terms. I'm sure it's more complicated than that, but I'm pressed for time). The most common side effect to removal is weight gain. Then there's bowel/stomach problems.

My mom has had terrible problems with intestinal issues since her removal in 99. There's no notice.. She has to go NOW. And there's no holding it to find a restroom, either. Can be rather embarrassing.