That is sort of a loaded question and a matter of personal taste. I like to mix the two, so that there is something interesting--and different--going on all four seasons. In one foundation bed, I have a group of evergreen holly close to the door, followed by a group of winter holly (which has no leaves, but nice red berries in the winter) and then a grouping of azealeas. In front of those plants is a multi trunked crepe myrtle (which has wonderful pealing bark and leaf-less form in the winter) and native perrenials that bloom in early summer and then late summer.

I think this is too general a question to get many responses. If you're asking what are the most common plants is use today, I'd simply walk around any neighborhood and see what is there. Another way to see what people are planting is to visit a few nurseries. Either ask what are the big sellers or see what plants are sticked in large quantities.

I think the most typical foundation planting involves small evergreen shrubs and a few eaily grown perennials or groundcovers amid a thick bed of shredded, dyed bark mulch.

Yeah,I'll ask my supplier. Thanks.

Foundation plants are highly subject to the whims of fashion. I think this mainly originates in the nursery trade, where there is a strong tendency to try to have something new in stock. So breeders develop new varieties to have something new to offer, nurseries order them because they are new, and customers buy them because they are in stock. Some of these new ones may be good plants in the long term, and some won't, but you don't know which is which until years later. You can tell the age of a development by the types of plants the developer planted, I am sure. Individual homeowners plant a more random selection of plants than developers and large landscapers.