fold change (how to represent it) - (Sep/08/2012 )

I was wondering how to represent fold change for qPCR data. Should it be log scale or linear scale.
I saw some paper showing data a fold increase (or decrease) of mRNA. Lets say the control value is 1 and the treatment cause it to go down say 0.259, what will be the right way of representation; and also if the treatment value is 4.
thank you in advance
vg

The easiest way is to plot a graph with the X axis on no change then draw bars above and below for +/- change respectively. Like figure 9 here