We were lucky enough to get an Azerothian ton (they're like twice the weight of normal tons, don't you know) of news about Wrath of the Lich King at Blizzard's Worldwide Invitational this weekend, and hidden in the Death Knight hands on, there's a ton of great information about the way the class' summons will work. Most of the summons seem to be in the Unholy tree -- Death Knights will not only be able to summon the ghouls we heard about earlier, but will also be able to bring down a gargoyle and summon an insect swarm. But the ghouls are what we're most interested in -- Army of the Dead is a level 80 spell (with a 10 minute cooldown!) that will summon a "legion of your best ghouls to fight by your side."
And our question is: how is this going to work? Obviously the ghouls won't actually work as pets as in the way Hunter or Warlock pets work, but surely they'll have a little more control implemented than the Druid's treants or the Priest's shadowfiends, right? As far as I can remember, we've never actually controlled multiple pets before -- are we going to have one bar to control all three with, or will we mark a target as they're summoned? It would seem that with a tanking class like the Death Knight, more focused pets would be a necessity in some cases.
Or maybe our ghouls will be as mindless as ever, and after we hit a button to summon, they'll just head for the closest thing that looks like it might have brains to eat. Hopefully the Death Knight's ghouls will be a bit more interesting than that (there was a rumor a while back that you'd be able to raise your fallen group members as ghouls, though I don't see that spell in the hands on), and if not, I guess there's always other Hero classes to improve upon the pet mechanics.