The online catch-up TV service ranked as the 80th most visited website in the UK, peaking at number 62 on New Year's Day.
"The BBC heavily promoted iPlayer on TV and in the press over the Christmas period and it seems to have paid off," said Robin Goad, UK director of research at Hitwise.
"Searches for 'iPlayer' increased 15-fold over the past month, and 18 per cent of the site's traffic came from search engines last week."
Despite the increasing adoption of the iPlayer service, YouTube maintained its position as king of internet video, accounting for 8.75 per cent of all UK internet visits to entertainment websites, 12 times as many as the iPlayer site.
"The average visit time for iPlayer is currently just under nine minutes, compared with almost 20 minutes for YouTube," said Goad.
"People are currently in the testing phase of many of these new services, but all of the main terrestrial broadcasters now have viable online TV services, and people are really starting to use them.
"Sites such as iPlayer also have a broader demographic reach than YouTube, particularly with regard to older users.
"Bearing these and other developments in mind, 2008 looks set to be the year when online video truly goes mainstream in the UK."
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