Furthermore, the reminders would flicker between the time remaining and the start time for the event at such a fast rate that it could not be read... (clearly a bug)
What is the solution? Go to Settings>Notifications>Calendar and disable Notification Center. You can still have the "alert style" set to Banners, or Alerts and you will still receive notices about your events, but it will not BUILD a summary in the Notification Center drop down screen. This is where the BUG exists.
So, it appears that Notification Center has an endless loop in collecting the calendar events from Exchange and this is burning up our 4S batteries. Once you stop the madness from Notification Center, your iPhone 4S will perform as advertised.
This suggestion has been met with a mixture of "I don't know, man" and "it worked!"
But until we hear some official word from Apple about the source of the problem (and let's assume it's not "whiny, complaining customers") and a solution, we can only speculate.
If any iPhone 4S owners can shed some light on the issue, feel free to comment (or complain) below.