BBC One's EastEnders emerged as the most tweeted about programme, in a survey first reported by New Media Age.
The soap's Christmas Day episode, which pulled in final ratings of 11.33m viewers, received more than 1,000 tweets per second.
The findings, from Starcom MediaVest Group (SMG), measured the number of tweets sent with the hashtag or with mentions over the period of the programme's live broadcast, against BARB and Sysomos viewing figures.
Overall, the BBC beat ITV in the poll, with the likes of Absolutely Fabulous, Outnumbered and Strictly Come Dancing also making the top ten.
Downton Abbey was the most popular ITV series in fourth place, while Coronation Street charted in ninth position.
"The growth of social media combined with connected TVs is opening up a brave new world of opportunities for brands to be part of the conversation with viewers," said SMG CEO Stewart Easterbrook.
Last month, it was reported that Hugh Laurie's US medical drama House was the most-discussed show on Facebook in 2011, followed by Two and a Half Men and The Simpsons.
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