Parliament has convened for its first sitting after the election, even though there are three MPs yet to be declared for the 111-seat chamber.
In widely-expected news, O'Neill was re-elected as PM this afternoon in a 95-12 decision.
Theodore Zurenuoc of the Sir Julius Chan-led People's Progress Party was earlier voted in as speaker.
According to recent reports, Zurenuoc was nominated by United Resources Party leader William Duma and seconded by Triumph Heritage Empowerment Party leader Don Polye.
The new speaker won with 88 votes compared to 17 for the PNG Party's nomination of Francis Marus - providing a solid indication that the O'Neill camp has at least 88 MPs behind it.
The last speaker, Jeffery Nape, was one of the high profile victims of the 2012 election.
While PNG Party leader Belden Namah retained his seat, he is unlikely to retain his deputy prime minister position and is destined for opposition.
O'Neill's victory will finally resolve some of the key matters of the lengthy political and constitutional crisis which emerged when O'Neill became a parliament-elected PM a year ago.