I think most peoples definitions of controller and striker are a bit off.
Most strikers seem keen on two things: stealth/ambush abilities, and massive damage to one specific target at a time. So a rogue striker is more likely to hide in shadows and sneak attack a specific target (usually the one the fighter is engaging as his role in defender). A ranger is most likely taking the scout's former role of "moving sniper" using his skirmish and ranged attacks to pick off weakened targets while constantly moving around the battlefield.
A controller is more keyed to three major focuses: area of effect damage (cones, bursts, lines), battlefield/terrain control (pushing foes back, creating walls, laying spelltraps) and creature control (charms, summons, necromancy). So while the fighter is beating on a foe and the rogue is sneak attacking to take it down quickly, the wizard is laying down cover fire (magic missiles), launching area attacks (fireball), keeping other foes from overwhelming the fighter (web, wall of ice) and/or directing magically controlled minions to aid in combat (charmed goblins, summoned celestial badgers, etc)
So then what might the differences be in wizard and warlock? A wizard seems the wizard might be focused on the "traditional" trappings of wizardry: summons, fire/ice/thunder magic, charms and illusions, etc. A warlock is much more the "dark, evil twisted" caster: they don't summon monsters, they summon undead minions. They don't use fireballs, they throw hellfire blasts. They don't toss out a web, they summon tendrils of shadow from the netherworld to hold fast their foes. They might have other differences: warlocks might excel at damage spells but wizards have an edge in divination and buffing spells. However, the two can sub for one another (much better than their 3.5 incarnations do) and are a lot more flavorful choice than book learning/spontaneous was...
Additionally: a warlock may gain no bonus out of the traditional wizard trappings (orb, staff, wand) or have no orders of their own (like the Emerald Frost) to join...
Of course, thats all wild speculation...