Christmas trees, like other trees, have different shapes and qualities. The most favorite Christmas trees basically have a pyramid or cone shape that make them more popular than others.modern Christmas treeThese include the Douglas, Fraser, Noble and Balsam firs, and the Scotch, Virginia and white pine trees. These evergreen trees all have one or more excellent features related to shape, color or sheen and fragrance, which makes them favorites to be used for Christmas trees and consequently are bestsellers.