QUICC is the abbreviation of QUad Integrated Communications Controller. The original QUICC was the 68k-based Motorola 68360. It was followed by the PowerPC-based PowerQUICC, PowerQUICC II, PowerQUICC II+ and PowerQUICC III. Early chips used a separate RISC engine to control the serial interfaces. Enhancing performance in these slower speed designs. The PQ2+ and PQ3 designs were the first in this family to offer Gigabit Ethernet speeds using more conventional ethernet controllers without the need for a RISC co-processor (there are some exceptions, such as the 832x bridge chips).
These chips have many integrated devices/controllers and were directly targeted at the Telecom industry, but they are still used in other applications as well. The technology has been the backbone of many Motorola Celluar Base stations. I saw hundreds of CPUs in a single cell to manage the network traffic.
The PQ2+ chips have moved into other directions as well. Many designs now have SATA controllers for SAN based applications. But networking will always be their strength.
As you would expect, these are Carrier Grade products and Linux dominates as the OS of choice. Every current Freescale PQ CPU/board comes with a working Linux environment. But Freescale continutes to offer MQX for PPC (a true RTOS) on a growing basis.