Voted for the War Mage, for mechanical issues, and flavor ones. (I prefer versatility to specialization).
As for the Heroes of Horror classes...
Dread Necromancer is pretty much what the name advertises, a caster who specializes in reanimating the dead and commanding/bolstering/generally having an army of undead around, and little else. Has a decent skill list including some stealth skills, light armor and weapon profs, minor DR that scales up with levels, and at 20th level, you become a Lich.
Archivist is the religious scholar class...an Int-based Divine Spellcaster who studies ancient tomes, knows the lore of the church, and of it's foes. The archivist's main cool ability allows it to aide the party against foes it has researched by vocally informing the party of the creature's strengths, weaknesses, and likely tactics, even during a battle, granting bonuses to attack, damage, saving throws, etc. to it's allies (which increase with level. It's the divine equivalent of a bard, with a dash of the know-it-all wizard-type.
