I wonder what they're gonna do with the Defiler abilities. With Zerglings now being able to turn into Banelings (I really hope they change that name), Dark Swarm + Banelings seem pretty overpowered. But I suspect they're not going to keep most of the original spells. I'm also worried about balancing the Mothership with everything else. That right there is like the ultimate support unit. Another thing I'm worried about is the usefulness of fixed positional units/structures (Seige Tank, Reaver, defensive structures). Blizzard has really shifted the game to something really fast-paced. With the Reapers, Stalkers, charging Zealots, etc., I think the traditional heavy fire support units (Tank, Reaver) are greatly downplayed and almost seem like they're going to be regulated to just a defensive role. Traditional fixed defense structures will also probably take a backseat to a more mobile defense network. I can almost envision fixed defenses being useful for like five minutes before enemy units start leaking in from every corner of the base, raping cannons, bunkers, tanks, etc. Of course, Blizzard has had a record of being able to balance games, so I hope my worries are unfounded. Yeah, I can totally see Ultralisks acting as a unit analogous to the Protoss' Colossus. I suspect going to take up the same supportive role that the Colossus was playing to the Zealots, in the gameplay video, except with Zerglings. I can also kind of see the Goliath being redesigned to become a heavy support unit, like the Colossus or Ultralisk may be. Of Course, it seems like Blizzard's going for a less conspicuous way of balancing the three powers. And finally, I doubt they totally removed the Dark Templar as a unit and replaced it with the Stalker, since Zeratul's seen in the artwork as a regular DT.