We compare the predictions for the form factors f_+^{D->pi,K}(0) from QCD sum
rules on the light-cone with recent experimental results. We find
f_+^{D->pi}(0) = 0.63\pm 0.11, f_+^{D->K}(0) = 0.75\pm 0.12 and
f_+^{D->pi}(0)/f_+^{D->K}(0)= 0.84\pm 0.04 in very good agreement with
experiment. Although the uncertainties of the form factors themselves are
larger than the current experimental errors and difficult to reduce, their
ratio is determined much more accurately and with an accuracy that matches that
of experiment.Comment: 12 page