A new survey suggests that three quarters of YouTube viewers would visit the site less often if the video sharing website placed ads before clips.

The Harris Poll questioned 2309 US adults in December last year.

The results found that nearly three-quarters of adults who frequently visit the site say they would visit it a lot (31%) or a little (42%) less often as a result.

At the time of the survey YouTube hadn't announced that it was planning on showing its viewers adverts before video clips.

The survey did however find that the airing of TV episodes with commercials on their TV network websites was acceptable. Nearly as many online adults (41%) say they have watched a video at a TV network website as they have at YouTube (42%). It seems like TV networks can get away with advertising more easily.

"Indeed, we have seen in previous data", says Burke, "that consumers as a rule are not averse to watching commercials online in order to catch an episode of a TV show they would otherwise miss. Yet those who are accustomed to finding and watching everything for free at YouTube may have developed a very different set of expectations for the site".

However as Google wonders how it will monetise the site, the survey found more bad news.

Of all frequent YouTube users, two-thirds (66%) claim they are sacrificing other activities when on YouTube. Although their visits to the site are most likely to have been at the expense of visiting other websites (36%), time spent watching TV is next most likely to have taken a hit (32%). YouTube also cuts into email and other online social networking (20%), work/homework (19%), playing video games (15%), watching DVD(s) (12%) and even spending time with friends and family in person (12%).