The Big Gamble - Lesley Stahl reports on the proliferation of gambling to 38 states and its main attraction, the slot machine, newer versions of which some scientists believe may addict their players. Brazil - As the U. S. and most of the world's countries limp along after the crippling recession, Brazil is off and running with jobs, industry, and resources. The economic juggernaut is poised to become the fifth largest economy in the world. Mark Wahlberg - From street thug, to rapper to actor and now producer, Mark Wahlberg has reinvented himself to the top of the Hollywood heap. Lara Logan profiles Wahlberg as he prepares for his most challenging role - a boxer.