I think it depends on what you do. And a lot has to do with signal strength. I notice considerable battery drain regardless of ROM if I pull in not only a weak signal but the dBm is consistently hovering over 80 and definitely over 95, pushing to what I think is a max of 106 in my area but in ICS and JB, it's more magnified.
Right now, my first full day on this ROM, I've been off my charger since 6:15 this morning, it is almost 4:30 (in Chicago) and I have 38% battery w/several app updates, listening to TuneIn Radio Pro, my Facebook notifications, pushing email from 6 accounts, texts and 3 long phone calls. Personally, I think that is impressive for ICS or JB...