I was just reading the "Ican't find a guitar" thread and was wondering what actually makes a guitar neck play fast? Is it some coating thats used? or maybe the wood?

The Ibanez Jem 7v has an excellent neck, feels smooth, plays fast and seems to give more definition on each fret when your fretting so that the frets seem more seperate (if you get what I mean)

I was just wondering what characteristics give the neck that quality.