Moving And Copying Layer Masks
If you wanted to move a layer mask from one layer to another, you used to have to jump through a few hoops, but in CS2 it’s much easier. Just click directly on the layer mask’s thumbnail and drag it to the layer where you want it. If you want a duplicate of a layer mask (rather than just moving it from one layer to another), press-and-hold the Option key (PC: Alt key) before you drag.
Hooray, thank you!