I recall a chat with an A319/320/321 pilot deadheading to YUL one day about autolanding. I suggested that it would be pretty useful in low visibliity situations, i.e. fog or snow. He agreed that it would help get the aircraft on the ground, but that ALL aircraft lack an auto-taxi-to-the-gate system. If visiblity is too bad to land safely, it may well be too bad to taxi safely, too.