Could my Cell Phone Battery be degrading?
Your battery is degrading from the charging station. The person whom makes your charging station probably expects you will use it before placing it in. They are then pumping a top-off charge into for 30 minutes when, although it did self discharge a little in those couple seconds, it should not get one.

It is possible the charging station is pumping way too much charge, but I am hoping the system can recognize it is almost done charging and go to slow-charge. From battery university about lithiums:


  No trickle charge is applied because
  lithium-ion is unable to absorb
  overcharge. A continuous trickle
  charge above 4.05V/cell would causes
  plating of metallic lithium that could
  lead to instabilities and compromise
  safety. Instead, a brief topping
  charge is provided to compensate for
  the small self-discharge the battery
  and its protective circuit consume.
  Depending on the battery, a topping
  charge may be repeated once every 20
  days. Typically, the charge kicks in
  when the open terminal voltage drops
  to 4.05V/cell and turns off at a high
  4.20V/cell.


There are phases to charging a lithium battery, as show in this picture:
http://www.batteryuniversity.com/images/partone-12.gif">

I have seen charging circuity before, when I have helped students build these, that will start with the heavy current phase and test the voltage, this means that if you unplug and plug in you can degrade the battery significantly.