From the BT4.1 FAQ and tech descriptions:
"Dual Mode Topology .. Device supports multiple roles simultaneously (Enables a Bluetooth Smart Ready product such as a smartphone, to act as a Bluetooth Smart Ready Hub and Bluetooth Smart peripheral at the same time)."
"Dual Mode Topology Enables a dual mode (BR/EDR-Low Energy) device such as a smartphone to act as a Bluetooth Smart Ready Hub and Bluetooth Smart peripheral at the same time. The device can then communicate with Bluetooth Smart peripherals on one side and another Bluetooth Smart Ready hub device on the other side."
I'm not sure why dual mode is needed, though?
Anyway, this hints at being able to build a mesh topology, I believe.
If so, will the DA14580 support 4.1 and also this mode? Or is there another solution for the chip? I understand CSR have a 4.0-based mesh solution.