ARM is well known as the maker of smartphone processors. Besides their popular Cortex processors, they also make popular GPU called Mali 400-GPU, which is used on many high-end smartphones including Samsung Galaxy S III.
Mali-450 GPU, the successor of Mali-400, will be launched next year for mid-range and low-end smartphone. Mali-450 will get improved performance (about two times faster than Mali 400) and new architecture that allow it to use more cores. As you can see on the picture, Mali-400 can have 1 to 4 cores, while Mali-450 can have up to eight cores.
ARM recommends that low-end smartphones with low processor performance should use Mali 400 GPU, while Mali 450 is made for mid-range smartphones which need more graphics performance than low-end smartphones. For high-end devices, ARM will provide Mali 6xx GPU, which have better graphics performance of course. Mali-T604 is the first Mali GPU in 6xx series and will be followed by Mali-T658.