After three years, she became a reporter for A Current Affair in Brisbane. A brief stint on a short-lived consumer affairs programme followed, before she moved to Sydney and returned to the news department, in late 2001.[2]
In 2007, McKinnon returned to Australia, as her husband David Gyngell was reappointed as the CEO of the Nine Network. Since then, she has presented the summer edition of A Current Affair. In 2008, she also regularly filled in on Nine News Morning Edition and Nine News Afternoon Edition. McKinnon is most famous for her interrogation of Corey Worthington in 2008 after he hosted a house party that led to gatecrashing, widespread chaos, and tens of thousands of dollars in property damage; the party and its aftermath, including the viral interview with McKinnon, have been widely speculated to have inspired the 2012 movie Project X, although this was never confirmed or denied by any of the writers or producers.[5][6][7][8]
In January 2009, it was announced that McKinnon will co-host Weekend Today alongside Cameron Williams, with Amber Sherlock and Michael Slater presenting the news and sport. The program began in early February, and was introduced to counteract Seven's Weekend Sunrise. The show later extended to Saturday mornings as well. She presented the show from Victoria the morning after Black Saturday, Australia's mostly deadly bushfires. In December 2009, she co-hosted the Sydney New Year's Eve telecast alongside Cameron Williams.
In 2012, McKinnon co-hosted Nine's award-winning coverage of the London Olympic Games and conducted the first live interview with Princes William and Harry. In 2011 and 2012, she wrote a weekly rugby league column for NRL.com. McKinnon is the editor of Australia's Favorite Recipes (2012), a cookbook which raises money for the charity Legacy and features the family recipes of ordinary Australians.