That is great feedback!!!!
Here is the link that convinced me to change my Thermostat
http://www.volvoxc.com/forums/showthrea ... -2009-XC70
I don't know if you still have it apart but if you do, I would recommend that you change the coolant hose and O-ring at the heat exchanger.
The part number can be found in this link. (Note: you can buy the Land Rover part if its cheaper)