Is Sensor tower still in the game?

[RamiZ]

As Rainbow says, it's going to be kind of hit-and-miss. It's also going to take more than a few Marines to trigger panic because no good player would ever try an unsupported attack with heavy units. Also, a player who is concerned could simply send a cloaked Ghost of Banshee out to scout the force, or drop a Scanner Sweep onto it.

This... Scanner Sweep together with Sensor Tower is just incredibly broken, you can see it even before beta starts...

[MattII]

Except that it isn't, because the Terrans don't get a mobile Scanner before the Raven, so they 'need' extremely good fixed sensors.