What does "enables control of DJ software without the need for special control DISCs "mean?

"Control DISCs" refer to the DJ software created by other companies that come supplied with a special software DISCs. Use of such DISCs also enable use of CDJ. (The signals from the DISC are routed to a computer via a special box.)

The MEP-7000 can be connected to a computer directly and therefore does not need such DISCs. This is a new feature.