Moynihan wrote in the Wednesday night thread that there are "plenty more" examples of "enormous factual errors, other cribbed passages, single or unsourced claims".
When asked by MacCallum if there could've been an attribution or footnote issue in the book, the former Times editor replied: "No, I don't think this is an issue at all."
"Many people from Vice have been taking issue with the book," she said.
"I think they don't like the portrayal of Vice although I think it's a very balanced portrait and I have a lot of praise for some of their journalists and some of their stories. I like their fresh approach to news."
Ian Frisch, author of "Magic is Dead" and freelance journalist, said after reviewing Moynihan's thread he did some digging of his own.
He compared what Abramson had written in her book about Vice's Thomas Morton, who Frisch profiled in 2014 for a magazine he founded, called "Relapse."
He then posted a similar thread, highlighting what appear to be passages and quotes lifted without proper attribution.
Although Relapse discontinued, Frisch said in an interview Wednesday night his profile on Morton was accessible for a couple of years on his website before he took it down.
"The whole situation is quite troubling, especially from someone who looked up to Jill and people like her as sort of the institutional leaders," Frisch said.
"I came up with, and I still do read the New York Times every single day. To go through those passages and to see how similar they were to my own writing - for her to attribute a quote to Thomas as if he was speaking to her, when he was speaking to me - it's just very disheartening."
Cary Goldstein, executive vice president of publicity at Simon & Schuster, which published Merchants of Truth, said in a statement it was "an exhaustively researched and meticulously sourced book".
"It has been published with an extraordinary degree of transparency toward its subjects; each of the four news organisations covered in the book was given ample time and opportunity to comment on the content, and where appropriate the author made changes and corrections," Goldstein said in the emailed statement.
"If upon further examination changes or attributions are deemed necessary we stand ready to work with the author in making those revisions."
The Washington Post reviewed end notes in the back of Abramson's book, which refer to pages where she used material that was not her own. There is no indication in the main text of the book showing which passages require attribution.
The Post could not review all of the citations, but found some citations that appear to refer to Frisch's work as well as examples pointed out by Moynihan.
The citations are not referenced in the passages where the sourced material was used, and instead are listed with page numbers and organised by chapter. They key to specific quotes or terms in the passages and refer to articles, websites and books.
"I've been shown that small snippets of my story have been credited in the endnotes, but the endnotes do not go into the depth of how much this section about Thomas relied on my article," Frisch later wrote on Twitter.
"She quotes Thomas as if he's speaking to her directly. This would not fly for a mag article."
Speaking with The Post, he added, "I worked so hard to stick to the foundation of journalism which is truth and accuracy, and it's difficult for me to see such brazen similarities in Jill's work and my own."
Abramson responded to the allegations again late Wednesday night, writing "I take seriously the issues raised and will review the passages in question."
She did not immediately return a request for comment.
