This was a change in 2005 from the 2002, and even provided a diagram, sinks with 12" or more behind it, on a straight wall will require a receptacle, sinks in a corner will require one if over 18" to the corner, also take note that the counter space for the wall space requirement starts at a point on the wall if you were to draw a straight line down the side of the sink to the wall aligned with the sink not the wall, see the diagram in 210.52(C) or the photo in post 1, I see this one getting mis-interpreted a few times, because they aligned the starting point squared with the wall to the sink.
And of course if the receptacle serves the counter top, it is required to be GFCI protected 210.8(A)(6)