it depends on your definitions of use. Moderate use to me is a few dozen texts, emails and facebook being checked/synced every 15-30 minutes, a couple of phone calls, and usually a bit of game playing/market browsing.
I can usually get 18-24 hours easy out of my battery, but I turn mobile network off when I'm not using it, especially since I'm usually in an area that has poor service. If I'm using it extremely heavy, like heavy web browsing and game playing, it probably drops to 12 hours or less...but I rarely do that.
It also depends on what ROM you're using, some are better on battery than others (more due to the kernel than anything). As well as whether you use the auto brightness, or how long your screen stays on when it's idle, and so many other factors that it's hard to pinpoint exactly what could be causing a person's battery to be performing worse than another's