Epica, Kingdom of Heaven. This might be the defining song for them: it's overlong, uneven, loaded with parts that are amongst the best in symphonic metal and others that are simply embarrassing- 'No, I don't want to go back NOOOOOOOooooo!!'
Coheed and Cambria, Mother Superior. I don't know if I can say it's their defining song, but it's amongst their best.
After Forever, Beautiful Emptiness It's too bad they broke up, Floor Jansen was probably the best female vocalist in metal.
Origin, Wrath of Vishnu. I'm not quite sure Origin is a band that can be adequately described. They aren't so much listened to as experienced. Either way, they're awesome.
November's Doom, A Eulogy for the Living Lost- 'I've watched for years as you failed at life Leaving behind the desperate cause Piercing sound that comes from miles below Rising from the depths to take you home' Into Night's Requiem Infernal is right next to Behemoth's Evangelion for my favourite metal album of the year. Of the two, INRI (I just noticed that abbreviation now) is the more atmospheric and beautiful, but it's also, as the lyrics quoted above indicate, depressing.