O'Neill has waited 20 months to taste success in the international arena, a period that has seen him oversee five draws and four defeats.
A 1-1 draw in Portugal earlier in the World Cup qualifying campaign hinted at potential but the lack of a victory and a string of disappointing home results was beginning to cast a long shadow over his tenure.
But the former Shamrock Rovers boss was able to reflect on a hugely satisfying performance in Belfast tonight, with Martin Paterson's 43rd-minute header ensuring a richly-deserved 1-0 win over opponents ranked 93 places higher than Northern Ireland.
"It was a great occasion for us and very satisfying for me personally. The players were magnificent from start to finish and deserved to win," he said.
"It was very sweet, very nice. I've had a few disappointments in the job so far, so to win makes it a very special night for me.
"I said in the past when you have so few games and such a long time between the defeats and the draws that you carry them around much longer than at club level.
"At least I've got a couple of weeks to carry this one around."
The unexpected win - Northern Ireland's first in 13 matches when Nigel Worthington's side claimed the rather lesser scalps of the Faroe Islands - was achieved without a number of senior players.
Manchester United defender Jonny Evans was a last-minute withdrawal with a stomach bug, Kyle Lafferty failed to travel with an Achilles problem, Chris Brunt was suspended and Chris Baird was not considered having yet to sort out a new club.
A number of players got their chance as a result, but it was the new forward pairing of man-of-the-match Paterson and the impressive Jamie Ward that shone brightest.
Paterson, whose only previous international goal came from the penalty spot in a friendly against Finland, could have had a second had it not been chalked off for a marginal offside, while Ward struck the post with a fierce drive.
"It was a new combination and it worked well for us," O'Neill admitted.
"Martin was brilliant. I thought he was excellent against Israel in the last game too and we maybe didn't give him the service.
"I was delighted for him. It was a great header and he was up against two centre-backs with about 160 caps between them who have the World Cups and European Championships.
"Jamie Ward was outstanding too. He was excellent with the quality of his play and his intelligence on the ball."
"It was an excellent performance, the team were magnificent."
Former England boss Capello, who will find it hard to justify a contract reportedly worth nearly £8million a year if he does not steer Russia to the World Cup in Brazil, was shocked by the home side's performance.
Having beaten Northern Ireland 2-0 in Moscow in his first competitive outing in the post and scouted them since, he was not prepared for the level of intensity they showed tonight.
"I never saw the Northern Ireland team play so fast, so strong. I thought it was the best this team has played today," said the Italian.
"I saw three games they played before this game and they never ran so far, so quick. They never pressed this tight.
"I think they played better than us. Their victory is because they played better than us...that is all.
"They played with speed and determination. they were always first to the ball. It is the best game I have seen Northern Ireland play.
"They played so fast, so hard. It was difficult for us."