Well, officially it is called the Bay Adelaide Centre (it will include all 3 towers when built),
Though it could have been called KPMG tower/complex/watever, as it is the largest tenant in the building (which is why they get a logo atop the tower), this building is a "phase 1 out of 3" sorta thing.
I like the name Bay Adelaide Centre better... it sounds classy
They have been calling this tower Bay Adelaide Centre West, and I imagine that name will stick. If they wanted their name on its title, KPMG would have bought naming rights by now.