iPhone: Reminder About Push-associated Power Usage

Some users have been complaining that the battery life of their iPhone 3G was dramatically reduced following installation of iPhone OS 3.0. It seems that the firmware is draining more resources when the Push option is activated. It seems that the function does not enter sleep mode between the refreshing time set every 15 or 30 minutes, you should compare with manual mode too. This power draining issue was already present with the OS 2.0, but it seems that OS 3.0 did not really improve it.