Bump into Yummy Mummy No 1 in our local café after the school run. She is wearing a pair of sunglasses, a black mac and furtively reading a message on her BlackBerry. I walk up behind her.

“Listen very carefully, I shall say zis only once,” I whisper in her ear in my best ‘Allo ‘Allo! accent. “Ze credit crunch will gobble you yet.”

“Lucy, you made me jump.”

“Have you got a job?” I ask her subversively. “Or is it part of a trend?”

“What do you mean?” she asks.

“Is there some kind of logical progression from Burberry to goji berries to BlackBerries?” I ask.

“I am awaiting important news,” she says imperiously, placing the BlackBerry face down on the table. My phone beeps and she looks at me expectantly, waiting for me to glance at the message. I resist, mostly to annoy her, but partly because I know it will be Sexy Domesticated Dad who, since he finished his book, has taken to texting me at the same time every morning.

“But a BlackBerry doesn’t really fit with that Seventies boho maxidress image, does it?” I feel quite pleased with my ability to encapsulate summer’s key trends in less than five words.

“It’s bobo, not boho,” she corrects me, still eyeing my mobile phone. “That is an important distinction in terms of how you frame your wardrobe over the next three months.”

I consider the key distinction between my summer and winter wardrobe and decide that it primarily involves switching from trainers to flip-flops.

“So is bobo sort of bohemian lite?” I ask.

“It stands for bohemian bourgeois,” she explains. “You can kiss strange men at middle-class music festivals but should go back to your yurt with your husband, or go long with a maxidress but go short with your bikini line. And don’t inhale.” Fortunately her BlackBerry beeps and she immediately picks it up.

“Oh, no,” she says repeatedly. “That’s just not fair.”

“Bad news?”

“The worst,” she says. “I’ve been refused the Gucci Hysteria bag and the Zac Posen clutch. The Russians have been given preference.”

“That’s the downside of globalisation,” I say. “Anyway it’s not as though you’ve been refused a mortgage. Or you’ve lost your job.”

“I don’t have a job or a mortgage.”

“Only last week you were saying that thrift is the new excess,” I persist.

“I’ve done thrift,” she says. “I’m describing all last season’s clothes as vintage. The handbags are an investment.” I raise an eyebrow. “Since the credit crunch, I’ve taken a long position in handbags.”

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