Some racing engines and racing inspired engines use a single turbo mounted between the cylinder banks on the engine. That would help to make the engine more compact, and it could be an interesting option for vehicles with tight engine bays. I could see it being useful for some cars featuring transverse engines. Could a single turbo arrangement like that be an option at some point in the future?
Eventually, single turbos for dual banked engines will most likely be included. Check the FAQ.