IBM is to use the silicon-on-insulator (SOI) technology that is usually reserved for server processors in mobile phones.
According to LinuxWorld the new chips will be a 30 percent improvement on standard CMOS technology. By building it on a scale of 45-nanometer feature sizes, IBM will achieve higher performance than comparable 65nm chips.
The Cu-45HP (high performance) custom chip will be released in early 2008. As well as mobiles it will be put in switches and routers. It will also have 45-nm embedded DRAM (dynamic RAM) architecture instead of SRAM (static RAM) in the chip.
More here.