Telstra's new CEO Andy Penn is making his first public appearance of significance today since taking the reins at the telecom giant in May. He's delivering a speech in Sydney and although nothing major is expected, it's still Penn's first chance to step out of the shadow of his illustrious predecessor. David Thodey engineered a stunning turnaround at Telstra , extending its dominant position in the mobile sector, negotiating lucrative agreements with the government over the National Broadband Network, selling off non-core assets and cutting expenses.