Amanda Hess pretty much nails it about the dumbass Lane Bryant commercial controversy and the smoking hot LB model who's too good-looking and stacked for American to handle.
When I read about it, I immediately flashed on an old Glamour "Fashion Do/Fashion Don't" column that cautioned against wearing the sheer shirt/black bra combo (remember those?) if you were big-busted, because it'd "look slutty."
Outcries like this are about more than not liking fat (that model isn't fat)--they are about how narrow the prison of acceptable looks really is. You can't win.