Susie Rushton: Mean streets where even mayors get angry

If I was walking along a London street and passed a stranger being set upon by a gang of teenage girls in "hoodies" (don't they know snoods, rather than hoods, are hip this autumn?), would I cross the road to dash the weapons from their hands? This week, London's Mayor Boris Johnson chased away a group of "oiks" who were attacking Franny Armstrong, a film-maker, in Camden. Said attackers turned out to be 12-year-old girls, eliciting rolled eyes in some quarters. "I think it was Boris's good fortune they were women," huffed newsreader Jon Snow, who reportedly chose not to intervene when he saw a man attacking a younger woman in the street. By contrast, the Justice Secretary Jack Straw praised Johnson's bravery, allowing himself a little brag: "I've done it myself four times and you have a millisecond to intervene. It's very important the streets are held by law-abiding people."

So would I have a go? I'm afraid the answer is yes. I apologise, in advance, to friends and family because I know getting involved is risky, and could get me injured, resulting in requests for sympathy and hospital visits. It's not that I'm particularly charitable or even proudly "law-abiding". I'm just too nosy, too bossy and quick to anger to walk on by. Not traits a politician would admit to.

Rich playground is growing

I've noticed that Knightsbridge (not the place but the road that runs from Harvey Nichols, alongside Hyde Park to the Royal Albert Hall) is living up to its rep. It used to be a rat-run for buses, a corridor of concrete blocks. I walked along it yesterday morning and was startled to discover on one side of the road a gleaming edifice called Knightsbridge Apartments, looking every inch the Beverly Hills-style celebrity fort – complete with an oaf in a tinted-window Mercedes who almost ran me over.

Opposite is the building site that will soon become One Hyde Park apartments, which promises to include London's most expensive flat at £100m (with bullet-proof windows). Next to that is the year-old Mandarin Oriental Hotel, where Heston Blumenthal will open his first London restaurant next year; yesterday another three-star Michelin chef, Daniel Boulud of Daniel's in New York, said he would open a place under the same roof in spring. SW7 is a snapsnot of pre-crunch London. But will there be enough mega-rich citizens to populate it?

Ads nauseam

According to the advertising industry, all we want for Christmas are craggy old white men. Stephen Fry and John Sargeant will front the M&S Christmas campaign (with help from craggy old clay man and dog, Wallace and Gromit). Sven Goran Eriksson does keepy-uppies with a tissue ball in an excruciating new ad for Kleenex. Ant and Dec, who at 33 and 34 are craggy if you put them next to Jedward, inveigle their way into living rooms, Danny Baker-style, to find out why so many households love the Nintendo Wii. Has TV advertising taken a turn for the unbearable?