No Porcupine Tree???? Shame shame.... "Where We Would Be" is just amazing. Steven Wilson has such a great voice.
Several runners-up(both metal and not):
Emperor - The Wanderer(last song on Anthems)
(ummmm...) - Benighted
(ummmm...) - Harvest
Alice in Chains - Whale & Wasp
Amorphis - Summer's End
Iron Maiden - Hallowed Be Thy Name
Mazzy Star - Fade Into You
The Sundays - Wild Horses(Stones cover)
Nevermore - Forever (last song on DNB)
Stone Temple Pilots - Still Remains
U2 - With or Without You