i'm very happy with the battery life i get on 5.0.1 Although, when i first upgraded-my battery life was terrible. The next day i did a restore as new and only added my contacts, calendar and photos thru icloud, then manually synced my few apps & music i have through itunes. Adjusted a few settings within, and since then my battery life has been great.
My average is 1day/8-12hours standby with 7-8 hours of usage.