Can definitely recommend heated gloves. Just picked up a nice pair of Gerbing's in a recent VisorDown power buy at £100!
Cabling is a bit of a faff, threading it through your coat, plugging them in etc. But damned the're nice. Lovely and warm. Other night I had to go half way round North Circular and out into Essex, around 10/11pm and it was just a couple of degrees above freezing, loads of wind chill. Hands were lovely and warm. Was an enjoyable ride, rather than a grit your teeth get home fast affair.
Did get a spot of cool ness coming through if I clenched my fingers around the grips (rather than more forward over levers), but the heating elements compensated fine. Guess more surface area for wind to chill. But it was great, to get home and not have to lock and cover bike up with numb fingers...