If you use the column view in the Finder, dates are shown for all files and directories. By default, the dates are shown in a relative fashion so that dates like "Today" and "Yesterday" get shown in place of the ful dates as appropriate. If you want to change this behavior so that it always just shows a date, go to the View -> Show View Options menu. Near the bottom there will be a checkbox labeled "Use relative dates". Uncheck this box and you'll get a more consistent date format in the Finder.