Henry, who was forced from TVNZ Breakfast in 2010 after mocking the name of a Delhi politician and questioning whether then Governor-General Sir Anand Satyanand was a New Zealander, never expected to return to early-morning presenting.
"I didn't think I'd ever be working in that slot again, let alone in New Zealand," he told The Diary.
Read more: Paul Henry to get 'lots more money' for new role.
Meanwhile, social media has been ablaze with comments from the public.
Lush has had a lot of support on Twitter, with fans telling of their upset about losing him to Henry. One fan wrote: "Can't believe that you won't be my commute buddy. Are the bosses crazy? Won't be listening. Off to library for an audiobook."
Another fan was more blunt, saying: "What sort of knuckle draggers would replace Marcus Lush with Paul Henry in anything?"
Sacha McNeil
• Daughter of retired journalist Bob McNeil.
• Has been a journalist for about 15 years, working for TVNZ and TV3.
• Was a presenter for late-night news show Nightline before its cancellation last year.
• Has been presenting TV3's Firstline breakfast show with business journalist Michael Wilson.
• This will be the second time her job has been affected by a change involving Paul Henry.
Michael Wilson
• Considered to be one of the country's top financial news commentators.
• Has been a journalist since the 1980s.
• Has worked for news agencies including TV3, TVNZ, Radio NZ and the National Business Review.
• Firstline co-presenter in last year.
Janika ter Ellen
• Studied political science and media studies at Victoria University.
• Was a reporter for 3News, Firstline and Nightline for three years.
• Was named as presenter for the new Paul Henry Show in December.
Hilary Barry
• Took over as co-anchor for TV3's 6pm weekday news bulletin in 2005
• Joined the channel in 1993 from Radio New Zealand
• Started on RadioLive's breakfast show in 2009
• Has won several radio and TV presenting awards, including best news or current affairs presenter at the 2011 Aotearoa Film and TV awards.
Marcus Lush
• Began hosting RadioLive breakfast in 2005.
• Presented a number of television shows including Off the Rails, South and North.
• Has hosted ZM's breakfast show.
• Also appeared on TV2's Newsnight with Alison Mau and Simon Dallow.