So after some testing today, I've concluded that the fan activity is due to the wireless card. When I connect to my router via copper, the fan doesn't even come on when I'm surfing. Switch to wireless and it sounds like I've got a swarm of bugs in my laptop.

I've even tried knocking down the transmit power to minimum to no avail.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated