Most day's, I work in a basement at work... and my phone has TERRIBLE reception...
I take my phone off charger around 4:30 every morning and I'll be down to ~ 30% by ~ 2:30 in the afternoon... (but that's again, with very crappy service). That includes having bluetooth connected for ~ half an hour on the way to work, and being connected to wifi while @ work, checking e-mail, and facebook periodically, playing card games at lunch time, and periodically texting with my wife during the day...
Today I spent ~ 3 hours down stairs, and the rest of the time in a different building and had ~ 68% battery left by ~ 4:30 pm...
During the weekends, I usually see around 25-30% battery drain during a full day... but there's minimal phone use during that time.