It is possible that you are having these issues because you installed the MacBook Pro SMC Firmware Update 1.3 by mistake:
*
http://support.apple.com/downloads/MacBookPro_SMC_Firmware_Update_13*
I remember when this was released that PowerBook G4 owners were seeing this update via their Software Update application. Sometimes I just install those updates without closely reading what they are for exactly. Anyway, I know it says for high work loads, but you would be surprised how easily the fans will turn on high just from simply web browsing.
I suggest that you first try resetting the PMU:
*If the computer is on, turn it off.*
*Disconnect the AC Adapter and remove the computer's battery.*
*Press and hold down the power button for 5 seconds and then release the button.*
*Reconnect the battery and AC Adapter.*
*Press the Power button to restart the computer.*
If the above works for you (great), if not, try resetting PRAM and NVRAM:
*Shut down the computer.*
*Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.*
*Turn on the computer.*
*Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.*
*Hold the keys down until the computer restarts and you hear the startup sound for the second time.*
*Release the keys.*
If the above works for you (great), if not, try archive and installing:
*
http://support.apple.com/kb/HT1710*
If the none of the above worked for you (not so great), do the following:
Go to your closest Store next week after making an appointment with a Mac Genius:
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http://www.apple.com/retail/geniusbar/*
I hope that I helped you solve your problem, but do post back if not and I will help you narrow down what is going on even further. Personally, I feel that I am better than going to see a genius because most of them are just trained for Intel machines these days out in CA, where as, I know all the way back to PPC and Mac OS 7. Best of luck.
