You could place digital cameras in either checked luggage or carryons. Digital media is unaffected by the higher radiation levels that are used in scanners for checked items. But if I were you, I would put it in my carryon as TSA may open your checked luggage to complete its inspection before being on-loaded into the cargo bins. That way, if its in your immediate control you will always know where it is. Also it isn't good practice to place expensive items in checked luggage as things have been known to disappear with TSA screening...
DON'T put your camera in your luggage!!!!! DON'T put anything of value in a suitcase if you want to see it again. Have your camera in your carry on bag.