This is a graph of the soda can that was left on the counter to warm up without the koozie.  If you notice there is a glitch in the data around 1485 seconds.  This was due to me adding the tape to the setup.  I realized that I had lifted the probe off the bottom of the can by using the plastic fork setup, but realized and thought of at this point that it was touching the sides of the can.  This is where I fixed that and added the tape.  I think that since it was not touching the sides anymore that it cooled a bit when it was moved in the liquid in the center of the can.  Thinking about the way heat is transferred, from warmer to cooler areas, the middle of the can would be cooler still than the outside of the can that was in direct contact with the warmer air around the can.  

The lowest temp it started at was 4.7 C.  The highest temp in the 30 minutes (1800 sec) it reached was 9.4.  It ran a little longer than I wanted to and did go up to 9.9.