The Illusionist would be pretty awesome....
So we've got:
Cleric: Divine Leader
Fighter: Martial Defender
Paladin: Divine Defender?
Ranger: Martial Striker?
Rogue: Martial Striker
Warlock: Arcane Striker
Warlord: Martial Leader
Wizard: Arcane Controller
I don't think the Ranger is a Striker. It'd step on the rogue's toes too much. He *could* be a martial controller (aforementioned arrow abilities making sure foes don't move around). A divine controller would make sense, and a Druid, a creature who manipulates the land and creatures in it, would make a GOOD controller.
The Illusionist would be cool. But I think my money's on the Druid. And it *should* be the druid. Part of the reason that might not be mentioned yet is because they're still tinkering with the druid's fiddly bits a lot, figuring out how Wild Shape should work and how the Animal Companion thing is going to work, and how the spells will influence the battlefield.
Even if it's not the druid, it'll probably be Divine. We don't have a Divine Striker yet, so if the Ranger is a controller, a Divine Striker would go over well.
Though, actually, I wonder a bit about the Warlock. Could it be powered with Divine rather than Arcane? Making pacts with powerful outside entities sounds more like what a cleric does with a deity than what a wizard does with a tome (or a sorcerer does with the blood).
Speaking of Sorcs, we've heard them mentioned a bit, too, so we know they're at least in the early phases. They could be Arcane Leaders (a high Charisma would do them good in this respect).