  The dominant theoretical uncertainty in extracting |V_td/V_ts| from the ratio
of branching ratios R=B(B->(rho,omega)gamma)/B(B->K* gamma) is given by the
ratio of form factors xi=T_1^{B->K*}(0)/T_1^{B->rho}(0). We re-examine xi in
the framework of QCD sum rules on the light-cone, taking into account hitherto
neglected SU(3)-breaking effects. We find xi=1.17 \pm 0.09. Using QCD
factorisation for the branching ratios, and the current experimental average
for R quoted by HFAG, this translates into |V_td/V_ts|^HFAG_{B->V gamma} =
0.192 \pm 0.014(th) \pm 0.016(exp). This result agrees, within errors, with
that obtained from the Standard Model unitarity triangle, |V_td/V_ts|_SM =
0.216 \pm 0.029, based on tree-level-only processes, and with
|V_td/V_ts|_{Delta m} = 0.2060^{+0.0081}_{-0.0060}(th) \pm 0.0007(exp), from
the CDF measurement of B_s oscillations.
