Online video sharing sites are reaping the benefits of the ongoing writers' strike in the US.
YouTube hosted a presidential debate in the summer
According to net measurement firm Nielsen Online, some online video sites have doubled their audience since the strike began at the end of October.
The news comes as US-based Pew Internet Project highlights a more long-term growth of video sharing sites.
Its study finds that the audience to sites such as YouTube has nearly doubled in the last year.
According to Pew Internet nearly half (48%) of US net users visited a video sharing site during 2007.
On a typical day, some 15% were either watching or posting video.
The on-going writers' strike has meant that many popular programs are currently off-air in the US and, according to Nielsen Online, this has seen Americans turn in large numbers to online alternatives.
Its figures show that YouTube's audience was up 18% in the two months after the strike started, and newer video-sharing sites such as Crackle have also experienced unprecedented growth.
In September and October, Crackle enjoyed an audience of 1.2m users which doubled to 2.4m in November and December, it found.
"That is greater growth than you would normally see in such a short period and the strike could be a possible factor," said Nielsen analyst Alex Burmaster.
The Pew Internet Project cites the spread of broadband connections and the widespread use of video by a variety of websites as factors for the longer term growth in audiences to video sharing sites.
Some 54% of American adults now have a high-speed connection at home, compared to 45% at the same time last year.
According to the Pew Internet Project, men are slightly more likely to use a video-sharing site than women - 53% compared to 43%.
But it is the young who are really driving the increase with 70% of people under 30 using such sites.
The dramatic rise in the number of video-sharing sites and other websites that incorporate video has had the knock-on effect of increasing the number of amateur video makers.
Some 22% of Americans now shoot their own videos, with 14% of them posting at least some of that video online.
Video sharing sites are also getting more closely involved in the issues that affect everyday Americans.
In the summer YouTube co-hosted a presidential debate with TV giant CNN.
The two-hour long broadcast featured all eight of the declared Democratic candidates and consisted entirely of questions that had been submitted online.