Yes, DFW is planning on adding more runways in the future. It has many spaces for expansion, and as of this minute has 7 runways. The Dallas/Ft. Worth area is growning at a tremenduous rate and the need for more airport space is very much a question. But, DFW can handle much more traffic, and handle more expansion than most airports can.
Hope that answers your question.
"[He] knew everything about literature, except how to enjoy it." - Yossarian, Catch 22