I love having the control over AutoCAD as you plot drawings, and the fact that _underscore is very easy to learn and adopt. I tried learning Inventor on 10 but the shock of not using _underscore was a little too much for me, and I've kinda given it up.
Another thing was the other day when our machinist mentor looked at one inventor image and said he didn't like the application. So...if he doesn't want to use it then I probably won't use it very much, either.
On another note, CNC mills, lathes, laser cutters, and waterjet cutters all use AutoCAD because it they are tools that work mostly in two-dimensional motions on an x-y axis.