The CompactFlash (CF) format was developed by SanDisk back in mid 90-ies, which makes this format more than 20 years old.
Nikon puts a lot of effort to promote the XQD format as the successor of CF cards.
New Nikon D500 as well as D5 both come with XQD memory card slots. The D5 will offer either dual CF slots or dual XQD slots. The company announced the XQD format in 2010 along with Sony and SanDisk and first used the new format in the D4 model.
In the future Nikon is planning to switch all flagship models to the XQD format memory cards completely.
The main competitor – Canon meanwhile hasn’t picked up the new format and is using in its camcorders CFast cards instead. There are some expectations that the new Canon 1D Mark II will offer a CFast memory card slot.