Chelsea were actually good before Ambramovich, Ranieri spent but not insanely and had the team being very good. Still to this day the backbone of the team and the best players were brought before Abramavich's big money came in, and most of his money, the majority, has been on players who have already left or barely play a part in the team. Frankly Chelsea could have spent about 40-50million and still ended up with exactly the same squad they have now, well, ok a bit more, but not outspending anyone else. The special one certainly has a special talent for buying players, didn't get many good ones though. Mourinho is just Harry Redknapp with a bigger bank balance, bought everything that was available and ditched the crap later on(then trying to bring the few good buys to his next club

).
Villa over the course of the year have played excellently, over the past 8-10 games they've got some lucky results and haven't played as well, but to be fair, they've got a light squad that have played a most likely higher number of games on average per player than any other top 4 team because Villa have little in terms of players to rotate in, while even Arsenal have a quite frequently changing line up. But they've still defended superbly recently, just not been as good offensively, that doesn't mean they got lucky, or were bad, just not as good.
The frankly, fully deserve to finish above us this year.
But O'neill has spent, this isn't the first year he's spent a lot of money either, just the biggest(i assume). But he hasn't wasted much money at all, and mostly the bigger priced players have all turned out to be good value, if not exceptional, like Young would command a 25-30mil fee if he was sold now but really is invaluable to the team, at 10mil he was one of the bargains of the past few years and well worth the cost.
I wouldn't mind knowing exactly who was in the squad before he arrived, and if many are still there because I doubt theres many.
The simply fact is that he hasn't spent "that" much and has done wonders with a team of good value players and got them performing brilliantly. Well done to him, and they've all worked very hard to get to 4th.
I said early on in the season that they could easily brake 4th this year, I even dared to suggest I didn't think 3rd/2nd were wrapped up and out of their reach either. getting towards the 2/3 mark and they are gaining on Chelsea/Pool and they are doing it while not playing at their peak. All 3 teams have the ability to play better, if any of the improve they can push on. I think Man U's depth is simply unmatched this year, but anyone can run into a dry patch.
unless Arsenal magically sign people who can instantly start instead of Diaby, Song and Denilson in the next two days, our chances of top 4 are almost non existant, well that or Wenger drops the underperforming players and stops being a moron, which seems even less likely to me than getting 3 world class players in before the window shuts.