Ali G himself, who is white (he's Sacha Baron Cohen, an ex-public-schoolboy), has taken on the persona of a "wigger", a white boy pretending to be a black dude, with all the right patois and gear.
Wearing his woolly cap and track suit, he interviews ex-CIA bosses and LA gang leaders. He asked the latter what they would do if their grannies knitted them sweaters in the wrong gangland colours. It is addictive stuff and has made Ali G a star, who has been chosen to make the alternative Christmas speech.
So why do I feel increasingly queasy about liking the guy? Because I am not sure what I am laughing at. I think that I am laughing at the stupid wigger mentality and at the interviewees, as they are made to look like monkeys. But I worry, too, that I am being drawn in to laugh at black street culture at its stereotypical worst. You also have to ask why no black comedian - and there are many who are just as talented and iconoclastic - ever gets to this position on British television.
This is typical of our relationship with the ubiquitous box, which is increasingly in the centre of all our lives. We do not trust it. We do not trust the people in charge of making programmes. In fact, they are always suspect.
So watching the telly is never just that, as we keep one inner eye constantly on the lookout for whatever will cause us fury and confirm yet again that British television takes our money but generally fails to deliver even a little of what we have the right to demand - real access, involvement, proper and diverse roles.
And this is not because we are paranoid. A number of detailed reports have reached the same conclusion; the latest of them was published by the Broadcasting Standards Commission this Tuesday. It accused television of lagging behind society and failing to reflect the multicultural nature of British society today. BBC's Tony Hall has just asked his producers to take action to remedy this.
There is a dangerous gap between who we are and who we think we are. For example, Coronation Street pretended for decades that Manchester was a white heartland, before Sayeed Jaffrey was brought in with much fanfare. He was, yes, you guessed it, an Asian shopkeeper who was in an arranged marriage.
At the same time a young black man was introduced, and he promptly used the opportunity to burgle the good people of the Street. Sanjeev Bhaskar is a brilliant comedy artist (you should see his Muslim Woody Allen once, before you die) so when does he get the space and respect given to Harry Enfield?
When the BBC ran a series on Southall, they used Melanie Sykes as the presenter. She may be a terrific ale-drinker, but she is clueless about British Asian life and to see her frothing cutely about nice curries and saris was stomach-turning. The Glasgow Media Group believes that should the two Trevors, McDonald and Phillips, and Meera Syal ever emigrate, the figures for black representation would fall by about 40 per cent.
I am not arguing that television should always show black and Asian Britons as wonderful and flawless. This is why I completely disagree with those who are currently kicking up such a stupid fuss over Channel 4's series on the chaos at Lagos airport.
I want television to stop ignoring or stereotyping us, but this also means that we will then be portrayed in all our variety, and as good and bad people. And when we reach that happy state, I can then let myself enjoy the talents of Ali G without all this brooding.