Eeeks! Right now, there is a difference of 17*C! I'm sure my computer would've made some noise when I was playing UT2004 just 2 hours ago, since I've set it to alert me (in the BIOS) when it hits 60*C. It's at 50*C now... I don't think those readings are right...
EDIT: Ok, Speedfan / Easy Tune 5 reports 34*C. Intel TAT reports 50*C. My BIOS reports 39*C. Hmmmmm....