Thanks, that's exactly what I was looking for! I imagine the definitions of the various Monster roles are available too, right? You've been a *big* help!
Yep- in essence:
An ARTILLERY monster is designed for ranged combat. It's about 2 points more accurate with ranged attacks than most creatures or its level are with their attacks, and its AC is about 2 points worse. Example: An archer; a monster whose primary attack is to spit acid.
A BRUTE has more hp, lower AC and (sometimes) lower accuracy than an average creature of its level, and does about 25% more damage. Examples: An ogre; a zombie.
A CONTROLLER has powers and abilities to help it control the battlefield. Maybe it leaves a trail of slime behind it that other creatures find hinders their movement. Maybe it moves enemies around with great wing slaps. Maybe it can cast charm spells or create a wall of thorns. Examples: An enchanter; an umber hulk.
A LURKER has to set its big attack up. Usually, it takes one round of setup (or good situational stuff) before it can unleash a devastating attack. Sometimes, it may have an ability that it can use to heal or gain extra defenses by not attackin. Examples: An assassin; a gargoyle that can turn to stone to avoid damage.
A SKIRMISHER is the "default" monster, but design-wise, is encouraged to move around the battlefield a lot. Maybe it has both melee and ranged capability; maybe it gets bonuses on charging attacks; maybe it can fly by enemies without triggering opportunity attacks. Examples: A quickling; a (typical) kobold.
A SOLDIER is the guy who holds your fighters off so they can't reach his side's squishier targets- just as your fighters do for your side. Soldiers tend to have ways to be "sticky", punishing enemies who try to get past them. They also usually have ACs about 2 higher than an average monster of their level, and sometimes have an additional +2 to hit. Examples: A black knight; a troll with a pole arm and plate armor.
There is some overlap here, obviously; for example, artillery and controller often look similar, and so can controllers and soldiers, as well as soldiers and brutes. But you can always just write more versions of the creature! That's one of the beauties of 4e monster creation.