I think a hard reset is called for! I'm using a 1020 and I've gone from 7am at 100% to 20% at 10pm. I've played about an hour of games, sent texts, whatsapp, web browsing, 6snap, news, wpcentral app, photos etc etc. Before the update the battery would have been dead within 7 hours! Battery app reads 1day 15hs at full charge! Plus the 3G reception where I live is poor, so I think that may be draining additional power, which could mean that the battery life could be even better!
EDIT: forgot to add Cortana is on & 16 apps running in the background.