  In this talk we present the recent calculation in all partonic channels of
the fully differential single jet inclusive cross section at
Next-to-Next-to-Leading Order in QCD. We discuss the size and shape of the
perturbative corrections as a function of the functional form of the
renormalisation and factorisation scales and compare the predictions at NLO and
NNLO to the available ATLAS 7 TeV data. We find significant effects at
low-$p_T$ due to changes in the functional form of the scale choice whereas at
high-$p_T$ the two most common scale choices in the literature give identical
results and the perturbative corrections lead to a substantial reduction in the
scale dependence of the theoretical prediction at NNLO.
