He will report to the board of DTV Services, consisting of representatives from the BBC, BSkyB and Crown Castle International.
His role will be to provide consumer and retailer support for Freeview.
Freeview recently announced that it had sold more than 300,000 set-top boxes in its first two months on air. In comparison, ITV Digital managed to shift just 116,000 boxes in its first four months on air.
Seaman joins DTV Services from NTL, where he was the product marketing director, managing the cable company's TV customer base of more than 2m subscribers.
Andy Duncan, DTV Services director and director of marketing and communications for the BBC, said: "We very much welcome Matt to DTV Services. He brings to the general manager post considerable experience in digital broadcasting and retail and will be a valuable addition to the Freeview team."
New research suggests that Freeview is proving a considerable boost to the multichannel industry, according to Continental Research's 'Winter 2003 Digital TV Report'.
Continental Research has found that awareness of Freeview, which launched in October 2002, has grown dramatically over the past six months. In July 2002, 39% of UK adults were aware of Freeview. Awareness in January 2003 has now risen to 58% and is particularly strong among men at 65%, compared with women at 51%.
This increase in awareness has also stimulated greater interest to buy into the Freeview service. Last summer, 14% of adults living in terrestrial-only homes were interested in the service at a price of £99. This has now risen to over a three-month period to 26%.
Dave Chilvers, director at Continental Research, said: "The figure of 26% of terrestrial homes interested in Freeview equates to a potential market of 3.8m homes. In addition to the moree than 1m homes that currently have access to Freeview services, a total market potential of around 5m at a price of £99 currently exists."
He added: "Just six months ago, when awareness of Freeview was lower and the service was not even fully defined, market potential was around 3m at a price of £99 and just over 4m at £49. This latest estimate shows how the availability and marketing of Freeview has significantly stimulated interest in this market."
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