The Forgotten Dreadnought appears to be roughly equivalent to the the GDI Kodiak and the Nod Salamander, with high anti-structure power and decent range. It is most likely they will be implemented in the Forgotten counter-attacks that were announced. It is unknown whether any upgrades to this unit will be added.
The Dreadnought has medium range and medium movement and seems to be very effective against walls and buildings. Extra caution is to be taken against these units since they were effective in destroying several bases and cities.