I think that gantt charts are useful for the majority of project types. They are a universal tool until the project manager puts in the specific project tasks They are a good tool for projects so that the design process can be planned out in an organized manner. You can see the large tasks and all of the sub tasks within it and identify how tasks are related. They keep everyone that is involved informed of what needs to be done when. I think that specific start and end dates are tricky to correctly estimate so if it needs to happen gantt charts can easily be edited.