Villa currently lie third in the Premier League and while they were dumped out of the FA Cup by Everton yesterday, are still heavily involved in Europe and tackle CSKA Moscow in the UEFA Cup on Wednesday.
Not only that, O'Neill has triggered the change in fortune with a largely English squad.
Villa supplied seven of the 23 players Fabio Capello named for last week's friendly with Spain and while the Italian cannot say so publicly, he is keen for O'Neill's side to continue their progress so his team gain more experience on the highest stage.
Even O'Neill's staunchest allies would not have expected the former Celtic boss to reverse Villa's fortunes quite so quickly.
Yet Nevin, who will be commentating on Wednesday's game for Five, claims the only aspect of O'Neill's work that has come as a surprise is the decision to abandon his favoured 3-5-2 formation.
"Martin's teams have always had a structure," said Nevin.
"At Celtic, the system rarely changed and he bought players to fit it.
"But he did not play that safe and secure system at Villa. He has been much more offensive.
"Maybe he realised you could not get up to the top level in England just playing cagey all the time. But it has certainly worked."
O'Neill's man-management skills have been the stuff of legend for years.
Yet the former Northern Ireland star surpassed himself this summer when he was confronted with the tricky situation of club captain Gareth Barry demanding a move to Liverpool.
It appears O'Neill played it exactly right as not only has Barry remained, he has been one of the most influential figures in Villa's rise to prominence.
"Barry looked as if he was certain to join Liverpool," recalled Nevin.
"He was stripped of the captaincy and suspended for a couple of weeks. But here is, still working his socks off for the manager.
"To arrive at that situation is a really difficult thing to do.
"You need fantastic management skills, although we have always known Martin is extremely good with players."
He is pretty useful at buying them too, with Nevin citing James Milner, Steve Sidwell and goalkeeper Brad Friedel "as good as he was five years ago" as his most astute purchases.
In addition, O'Neill has worked tirelessly with the likes of Gabriel Agbonlahor and Ashley Young, turning them from raw youngsters into international stars.
Yet, if you got an honest answer from O'Neill, away from the cameras and headlines, Nevin suspects the Villa boss would be at odds with his club's supporters about this season's priority.
"If you got Martin in a quiet corner, with the tape recorders switched off and asked him whether he wanted the top four or Europe, he would say top four," said Nevin.
"But you do not get choices in football.
"Martin doesn't know how the rest of the league is going to go.
"Arsenal and Chelsea might go on runs that eventually make that fourth spot impossible. He also knows the glory that would surround winning the UEFA Cup. If you are a Villa fan it would be extraordinary.
"Ask them what they want, fourth in the league or a piece of silverware they can look back on? In 20 years' time what will people remember? It is the trophy every time."