It was a smart move from a woman whose intelligence and guile have always sat uncomfortably with efforts by the tabloid press to categorise her as yet another, interchangeable, Met Bar blonde.
Ms Frostrup has, over the past few months, been in the news for an alleged romance with Chris Evans (false, say both sides), for being among the candidates to succeed Barry Norman on the BBC's Film 98 (still a possibility), and for being chosen to front a new Channel 5 talk show at prime time, 7.30 on a Friday evening - a big change from her last, Sunday-morning- with-hangover slot.
Almost overlooked, though, is Brazen Husky (chief executive and sole employee: M Frostrup), a machine through which she will be able to create and control her own brand.
At a time when television channels are proliferating and budgets on the big four are constricting, industry insiders agree that the importance of creating a coherent, saleable brand for yourself is becoming increasingly vital. "Look at the brands people like Noel Edmonds, Des Lynam and Chris Evans have built for themselves," says Mark Borkowski, a celebrity PR. "You know what you get with those names. You have to look at what you have, build on it, and recognise your weaknesses."
In her Portobello Road HQ, an airy studio with plenty of sofas and colourful coffee mugs, Mariella Frostrup is stretched out on a sofa, talking about her new company. "It's not empire building or a ginger, Planet 24-type thing," she husks.
The Irish-Norwegian takes a drag from one of many Marlboro Lights. Her new company, she says, is more to do with being a control freak. "It's to do with the culmination of eight years in TV. I've always written my own material and I wanted to start getting credit - or the blame, whatever."
Ms Frostrup refuses to identify her brand image - "it would mean thinking about myself for more than a minute, which I couldn't bear" she says, stalking to the kitchenette in search of another cigarette.
Soon, though, she does define herself, by default. "I've never been a bubbly blonde, I'm really bad-tempered," she says. "Women on TV are seen as interchangeable, whether they're newscasters, presenters or entertainment. And if you're blonde (which she isn't, quite: more mousy, as she's the first to admit) you get lumped together: a herd of cattle, a flock of sheep, a bunch of blondes. I think that's the word for it: a bunch."
And that is, partly, where the production company comes in. "There comes a point when you just want to control your own life. And people are less likely to come to you with a proposal for some sort of nonsensical drivel if you're known to be in charge of, writing and producing your own programmes.
"You have so much more control over what you do, from the guests down to the sofa fabric in the studio."
As a former bubbly blonde who has fought hard to be recognised for what she is - an intelligent and refreshingly natural TV presenter who happens to be an attractive woman - she is wary of anything to do with tabloid television. The plethora of new channels may give opportunities to people wanting to break in to the industry, "but unless you want to present a show for pounds 2.50, it's not something to do".
There is one proviso about the Mariella brand, though: asked if she would be where she is today if she didn't have a nice face, she replies instantly: "No. If I didn't have a nice face I would be respected but unemployed. That's an indictment of the sexism in the system."
Happy though she seems to be with Frostrup on Friday, which will see the customary array of guests being barked at charmingly and, she insists, unobtrusively, she hasn't managed to get complete control: "I'd never have chosen that name," she says with a genuine cringe. "I'm not the point of the show, the guests are."
Which points to an inherent contradiction in personality branding. Ms Frostrup says she sees herself as a journalist, a conduit between guest and viewer, her own experiences (she left school at 15 and her intelligence is of the streetwise kind) lending her a populist touch. But to succeed she has to be the point of the show, to prove to the powers paying her that the Mariella brand is both unique and essential, or else they could get someone else to do her job.
A publicist asked to "brand" Ms Frostrup once called her "the thinking man's crumpet" - which can describe anyone from Anna Ford to Francesca Annis. If Ms Frostrup succeeds in intelligently bringing the likes of Damien Hirst and Gilbert and George to the attention of people who would otherwise only have read about them in the tabloids - then she'll be a rare brand indeed.