MBP Dual core (2006) fans usage since Mac OS X update 10.6.7 Am I the only one who noticed this : 

since the last Mac OS X System update, the fans are quite often spinning at full speed, regardless of the activity on the computer. It happens even when there is not app running. I don't know if it's an heating problem or just the fans that are randomly triggered...

Does someone else encountered this weird behavior since a couple of months ?

EDIT : In fact, it seems that this problem has nothing to do with OS X upgrade. The problem is an heating problem and it related to some flash video reader that takes all the CPU power to display the video.
Airflow are certainly dirty. You can check it by opening your MBP. Find your model at iFixit and follow guides to access right and left fans.