Here’s a few screenshots of new terran starcraft 2 buildings as seen on a Korean media site:

Terran Tech Lab -not sure exactly what this does yet. Probably upgrades/prerequisite?

Here’s your basic supply depot. But seeing as how they are often used for base defense, with Barracks acting as a gate, Blizzard came up with a convenient solution:

…a supply depot that retracts into the ground that allows your units to pass! Genius!

Sensor dome allows you to detect cloaked units. Not sure why you would build this over a missile turret… perhaps it’s an addon?

The radar dome allows you to see enemy units on your mini map, I believe, but you can’t tell what type of units they are. Still, this could be pretty useful.

Last but not least, we have the Terran command center, or planetary fortress. It can carry up to 5 SCVs while lifting off, allowing for a jump start on expansions. In addition, it can be upgraded to “Planetary Fortress,” which gives it a weapon of some sort.
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the sensor dome blocks the terrain comsat station from being able to see the area wit its radar thing
you’d create a sensor dome over a missle turret because the new missle turrets can’t detect unless their in the range of a sensor turret.
the radar tower also detects units in the fog of war