RADIO / All I got was a lousy postcard: Robert Hanks browses through two oh-so breezy postscripts to Letter from America

When you want to say something considered and serious, you send a letter. When you just want to say a breezy 'Having a great time, the X is where our room is' - when, in other words, you don't want to think too hard about what you're going to say, then you send a postcard.

The distinction seems relevant when you consider Postcard from Gotham (Radio 4, Saturday). There's a suggestion in the title that Mark Steyn and his panel of New York luminaries are deliberately setting themselves up in hep young contrast to sobersides old Alistair Cooke and his fuddy-duddy Letter from America - they're a big 'Howdy' next to Cooke's genteel 'Good morning'. On the whole, though, the thing that strikes you about Postcard is how familiar it all seems. In form, it's a Manhattan transfer of Stop the Week (true, Mark Steyn's interpolations and links aren't as studiously scripted as Robert Robinson's; but what you gain in spontaneity you lose in persistent nervous laughter), while in content it's Cooke with jokes. The serious (Clinton, Haiti) is mixed with the trivial (Playboy hits 40, Elvis reported alive but under federal protection); but like Cooke, the trivial serves as a pretext for theorising about the state of the Union - this week, for instance, somebody came up with a rather neat insight about Elvis's importance lying in his status as the first truly proletarian star.

In this respect, Kennedy - NYC (Radio 1, Thursday), a self- styled 'hour-long radio informational lifestyle fantastico programme', is something of a breakthrough: a weekly exploration of Americana that makes no concession to the significant or the serious.

The ingredients here are all fairly familiar - Prozac ('In many ways, the Valium of the Nineties'), zany jobs (pet psychics]), celebrity stalkers (but don't worry - the only shooting they do is with a camera]]). The opening sequence, with its collage of radio stations, commercials, white noise, is a terribly cliched shorthand for 'We're now in America' (there was a rather similar sequence at the beginning of last week's Mixing It on Radio 3, reporting from San Francisco).

What sets Kennedy apart from the rest of the transatlantic reportage trade is the presenter, Kennedy herself: nothing to do with the airport, although the coincidence gives the title an extra dash of local colour (it's fortuitous that New York has an airport with a reasonable name - you can't imagine a programme on the London scene presented by somebody called Heathrow or Gatwick).

According to the publicity, Kennedy is a VJ, a 'video jockey'; and she lives up to every dire warning about the evils of the video age. For a start, her attention span is blindingly short, so that for her getting through the commercial break on television must represent the same kind of effort that, say, reading A la recherche de temps perdu does for the rest of us.

This shows up most in her interviewing technique, at times leading to awkwardness - last week, just as the pet psychic was getting deep into her answer to the question of whether pets can levitate (apparently they can), Kennedy barged in to ask if she should stop swimming. 'You are being very rude,' the psychic said. 'That's not the way to get ahead in life. When you get to the top, then you can be rude, but where you are now, darling . . . ' Fortunately for Kennedy, she has no embarrassment glands. On the other hand, she does have a pet iguana called Bergdorf, and could probably give an eight-week course of lectures in advanced wackiness without notes.

You couldn't justify Kennedy morally - it's far too greedy for experience and convinced of its own attraction. But there is something brilliant in its insouciance and its complete inattention to form; and you suspect that it has its audience sussed - it knows that half the listeners will be doing something else at the same time, and it really doesn't care. This is the byte- sized, electronic, information superhighway riposte to Alistair Cooke: e-mail from America.