on the 9700 when in and out of strong single I loose 7.5%/hour. But I charge every night at least so has not been a problem. Once or twice I did run out during the day.
I was having great difficulty with my battery on 9650 running BlackBerry 6. Discharge rate was all over the map, anywhere from 6% to 25% per hour, most commonly in the 8% to 10% rate. I switched to an extended battery and have kept it below 4%.
On my 9700 running OS 5.0.0.714 my discharge rate is between 2-2.2%. This is on moderate/heavy usage with Berryweather,CB Wallpaper Changer and MeterBerry running constantly. I am on WIFI at home plus UMA also for calls w/T-Mobile. I can make it through a full day of email,sms,SocialScope posts and checking out CrackBerry throughout the day as well and this is with the stock battery. No problems here,at least for now!
Posted from my CrackBerry at wapforums.crackberry.com