When Alcatel and Lucent merge later this year, Lucent chairman and CEO Russo will take the helm of the $25-billion-a-year maker of telecom equipment, which will have its headquarters in Paris and serve customers in 130 countries. Russo, 54, kept troubled Lucent afloat during tough times in the phone business. Now the unflappable New Jersey native faces more tough tasks: stitching together two corporate cultures and delivering a promised $1.7 billion in annual cost savings.