He told the Herald last night he planned to have interviews with each MP and have his new line-up ready next week.
Asked what his top three priorities were in the job, he said, "Working with my caucus colleagues to build a strong unified team that can take on the Government; addressing my mind to the structure and processes of the leader's office and some key staff appointments; and working with my colleagues to take the fight to John Key on a range of priority issues including jobs, housing and a critique of the Government's very transactional approach to business".
Commenting this morning on how Mr Cunliffe will fare as Labour's leader, the Prime Minister said he didn't expect he'd pose much of a challenge to the Government.
However John Key told TVNZ's Breakfast programme he thought he'd get more of a fight from Mr Cunliffe in the debating chamber than he'd received from David Shearer.
"There's no question David Cunliffe will be more articulate, actually that will put quite a lot of pressure on Russel Norman, who's been getting quite a lot of airtime as a sort of de facto almost leader of the opposition,'' Mr Key told TVNZ's Breakfast programme.
"So in a way it may change the split of Greens and Labour but I don't think it will grow what is effectively now the far left.''
Mr Cunliffe won the leadership contest with 51.5 per cent of the total vote of MPs, party members and unions, to Grant Robertson's 32.97 per cent. Shane Jones got 15.88 per cent.
Mr Cunliffe is expected to have discussions today with Mr Robertson. It is not known whether he will encourage him to stand as his deputy.
If that encouragement is not forthcoming, Mr Robertson's supporters say he will not put his name forward at tomorrow's first caucus meeting.
All balls are in Mr Cunliffe's court.
The caucus ostensibly votes for the deputy leader but realistically, the person needs to have the full support of the leader.
Mr Cunliffe said last night he saw it as a caucus decision.
"I have not made any indication of preference in any direction at this point," he said, but added, "I may consider those things more."
Mr Cunliffe is expected to leave finance spokesman David Parker in place but probably offer Mr Jones and Mr Robertson more substantial portfolios.
His first party conference as leader is just seven weeks away.
"It will be an opportunity to motivate our base and lay out our collective approach to winning the 2014 election."
Mr Cunliffe won 60.14 per cent of the membership vote, 70.77 per cent of the union affiliates vote and 32.35 per cent of the caucus vote.
Mr Robertson won a much bigger share of caucus support than Mr Cunliffe, 47.06 per cent.
Mr Robertson in his concession speech pledged "100 per cent loyalty" to Mr Cunliffe, now and into the future.
Asked whether he could rule out a leadership bid in the future, Mr Robertson said: "I'm 41 years old. Once David Cunliffe has done three or four terms as Prime Minister, you never know, it could be my turn then."
"This election has been a first for Labour Party members, MPs and affiliates. Now the result is known the EPMU believes it is time for the whole party to unite behind David Cunliffe as leader. The focus must now be on building a vision for a fairer New Zealand and winning in 2014."
EPMU national secretary Bill Newson
"This is quite an emphatic victory [for Cunliffe]. He did much better than I had expected in the caucus, and Robertson did not do as well as I expected." Former Labour Party president Mike Williams
"The jury's out as to what his leadership could mean for Auckland business. He's got a good understanding of the commercial world, but at the same time he seems determined to take Labour further to the left by already promising the likes of tax increases." Auckland Councillor Cameron Brewer