As readers of this column will know, that opposition is at its fiercest over highly controversial plans to hold the Games' horse events in Greenwich Park. 2012 organisers admit that much of the park, a Unesco world heritage site, will be closed for around ten months and trees will have to be "pruned." There will be no legacy.
The antis include the Friends of Greenwich Park, the Blackheath Society, the action group Nogoe - and, perhaps most importantly, opposition appears to be growing in the world of Olympic horse sport itself. Last month Zara Phillips, the former world champion, condemned the plans. Only three weeks ago, Clayton Fredericks, the current world champion, said: "I'm with Zara Phillips and many other riders - this site isn't the right one."
So it was surprising, last week, when the BBC's influential London news reported that opponents of the horse events at Greenwich had called a "ceasefire." The reporter, Adrian Warner, said that "after a year and a half of rowing," there was now an outbreak of "peace and tranquility," with opponents "realising that the games are probably going to come." The BBC website proclaimed: "Horse events venue row resolved" and announced that Greenwich residents had "accepted concessions for hosting the horse events."
This story has caused great anger in the Nogoe camp, and is now the subject of an official complaint to the BBC. "Nothing has changed," said a spokesman for Nogoe. "We have not called a ceasefire and we continue to campaign against the horse events every bit as strongly as before. Adrian Warner did not even contact us before he announced to the people of London that we had ended our campaign."
The campaigners are understandably concerned that their months of pounding the pavements, drumming up support, could have been torpedoed by a report which told tens of thousands of people in Greenwich and Blackheath, quite wrongly, that it was all settled. The supposed concessions, meanwhile, seem less than clear - amounting to little more than some minor re-routing in the flower garden.
Liz Coyle, chair of the Friends of Greenwich Park, was quoted in the BBC report as being "content that [the event] can be fitted in," something which has always been her personal opinion, but is not the view of her organisation.
Mrs Coyle is on holiday and could not be contacted, but her colleague on the Friends, Clive Corlett, told me: "She certainly said [to the BBC] that the Friends' position had not changed. We were a bit surprised to see the report. I'm not sure where they got that."
I'm not sure either - Mr Warner says that since his report is now the subject of an official complaint, he cannot talk about it - but I understand that the BBC man did genuinely believe that the Friends, at least, had softened their position.
Even so, there's also concern about what one local blogger - himself ex-BBC - called the "astoundingly one-sided" tone of the broadcast, complete with phrases such as "You can't accuse 2012 of lacking ambition" and the assertion that the horse events will represent "a giant leap for equestrian-kind."
The line that opposition over Greenwich is "fading" is, of course, one that Locog has been trying to push for months. But then it's hardly the first time our Olympic masters have resorted to lying to get their own way. Remember when the budget for the Games was supposed to have been £2.4 billion?
The BBC (and Warner), by contrast, have a reasonably good track record of scrutinising Olympic spin. What a shame it would be if that started to change now.