I remember the Chelsea v Hull game very well, KDB made a lasting impression on me from that match. He was fantastic, and also played either the match before or after to similar effect, and was possibly MOTM in that game too - and in both he was played centrally.
A lot of people have been talking about his inability to tackle, but I don't see that as too much of a problem. Firstly, he'll learn, and closing down players and blocking their pass lanes and intercepting is more effective than tackling anyway, unless a last ditch tackle is needed, or a crucial tackle on a playmaker, in which case it won't be up to him. Secondly, I remember a little ginger wizard over the road who didn't do too badly despite his inability to tackle.
Although, in saying that, the thought of playing a three man midfield including KDB and Yaya does worry me.