Christie married fellow Kiwi cyclist Jason in November, with her husband having twice claimed victory in the men's road race, including winning the title last year.
He'll defend that title tomorrow, but today, it was Georgia's turn to stand on the top step of the podium, having held off the peloton in a stunning ride on the Napier course.
"It's unbelievable - I never thought I'd be able to have this jersey on this year," she said.
"I'm pretty overwhelmed, the competition was amazing - I can't believe I stayed away.
"I was hoping to work with my teammates a bit, but I just kept my head down and kept going."
Christie attacked on the first of six ascents of the 'Hospital Hill' - a kilometre long climb at an average gradient of 4.8 per cent.
Catching early attacker Kirstie James, Christie went flying past and took a lead of over two minutes.
With a disorganised peloton behind, there were few riders taking control, and it wasn't until the fourth of six laps that they managed to reduce the gap. Several riders tried to emerge from the bunch without success, as the peloton finally picked up the pace.
Williams, who won the time trial yesterday, put in an attack in her quest to do the double for a second straight year, but she had every rider following her wheel, and couldn't get away from the bunch.
Her attack on the penultimate climb did manage to reduce Christie's lead to 13 seconds with a lap to go, and with 20 riders looming, the catch looked inevitable.
However, with Christie's parents on the side of the road, telling her not to give up, she pushed on. And with not enough cohesion in the chasing pack, and Christie finishing exceptionally strong, she held on for a superb victory.
