For years, it seemed the nearest that Sir Richard Branson would get to flotation was dangling from a hot-air balloon. His appetite for stock market flotations appeared to have disappeared from the radar with his disappointment at Virgin Group's listing, despite it earning him a place in the record books. His repurchase of the company for £248 million in 1988, after 20 months on the stock exchange, was then the UK's largest management buyout.

He blamed the decision on the poor performance of Virgin Group shares, which slid from a launch price of 140p to 83p despite a doubling in company profits. The earnings news was overshadowed by the October 1987 stock market crash, leaving celebrity backers such as Bryan Ferry and Phil Collins out of pocket and Sir Richard with a sour view of City practice.

"The delightful thing about not being a public company is that we don't have to worry about foolish analysts who say stupid things," he said when Virgin was back under his control.

Australian financiers had the chance to revisit this comment when Sir Richard launched Virgin Blue, the discount airline, on Sydney's stock exchange in December last year. Was analyst folly to blame for a 9 per cent rise in Virgin Blue shares, which were oversubscribed tenfold, on their first day of trade?

City-folk will next month get the chance to change Sir Richard's opinion of their credentials - and the entrepreneur will be keen to dismiss his complaints as hot air – as the roadshow begins on flotation of Virgin Mobile. What a difference 16 years, the creation of a booming mobile phone operator and a revival in appetite for technology stocks makes. Less than five years after it was launched, Virgin Mobile has attracted more than 4 million customers and, it appears, a stock market value of £1 billion. Sir Richard said this morning: "I am confident that, following the IPO, Virgin Mobile will go from strength to strength."

Still, any sensible analyst will want to know whether the estimated £250 million Virgin Group will raise from the flotation of the mobile subsidiary will go towards group activities or back into the telecoms business. The estimated £300 million debt which will be included with Virgin Mobile may not be huge by sector standards but on what terms was it written, and does the company have the cash flows to support it?

If, as some say, first is first and second is nowhere, then what are the prospects for the fifth-ranking UK mobile operator when giants such as Vodafone and mmO2 show no signs of losing their dominance? How will Virgin Mobile fare in the dawning 3G age which promises such competitive pressures as well as opportunities for snapping up rivals' customers?

The fear will be that the cash will be used to support other Virgin projects, such as a US internal airline Sir Richard is reportedly considering. He is unlikely, as at Virgin Group, to dig in his own pocket to rescue Virgin Mobile from any future City savaging.

Responsibility for the telecoms company's success lies in the hands of its bosses, Tom Alexander, chief executive and a former BT Cellnet director with significant credibility, and Charles Gurassa, a, er, travel industry expert who spent ten years at British Airways.

Plans to revive Concorde, support the first solo-piloted flight around the world, run a not-for-profit Lottery and break ballooning records, may bring Sir Richard a buoyant public profile.

But "foolish" analysts would be more relaxed if they could be sure of the Virgin Group's appreciation of the bottom line.