Nokia Siemens says that Network Controlled Fast Dormancy (NCFD) is the middle way between keeping your phone always active (drains battery life) or always idle (takes time), thus gaining both faster network response and better battery life. Nokia Siemens gives the following examples:
"Testing in North America found that our smart networks generate up to 50 percent less smartphone signalling, while one Middle Eastern operator found that smartphones on a Nokia Siemens Networks network had a battery life of 11 hours compared to six hours on a competing network."
Doesn't sound too bad and it seems that Apple is thinking the same. Only time will reveal its practical implementation on global scale, but Nokia and Apple fanboys have every reason to be happy.
source: Nokia Siemens Networks Blog via Engadget