Ok, let me make sure I have this clear.

If I'm going to use nodes to adjust an image,  I need to remove the gamma correction (using a color math node to raise the image to the 1/2.2 power {or is that taking the 2.2th root of the image?}), do whatever voodoo I need to do with nodes, then reapply the gamma correction to the result (using a color math node to raise the image to the 2.2 power) just prior to attaching it to the root node.

Do I need to do this to displacement/bump maps as well?

Thanks.