Speaking at the Sun Valley conference yesterday, the News Corporation CEO warned "be careful of investing here" in regards to Twitter and gave a staunch "hell no" when asked if he was considering selling struggling social network MySpace.
MySpace recently laid off a third of its staff worldwide, about 700 employees, and has been eclipsed by Facebook as the most popular social networking site in the US, a title MySpace held for more than five years.
Murdoch called Facebook a "directory" and "how they make money is another matter".
Marc Andreessen, a Facebook board member, revealed this week that Facebook is set to earn in excess of £500m (£309m) this year and will likely be posting billions of dollars in revenue in five years.
The Sun Valley conference, now in its 27th year, regularly brings together old media moguls and hot young start-ups to discuss the future of the industry, and negotiate the odd acquisition.
Yesterday, there was much speculation as to which company would acquire Twitter, seen to be a darling at this year's conference.
Yet, John Malone, chairman of Liberty Media, shared Murdoch's scepticism about Twitter and said "I don't know if it's monetisable".
Regardless, Twitter, now with 30m members, about a quarter of MySpace and Facebook's member base, has skyrocketed in popularity in 2009, growing about tenfold since last year's conference.
The website has become a virtual stopping-post for web users to discuss breaking news.
This week, during Michael Jackson's memorial service, all ten trending topics were related to Jackson at one point during the day.
The term 'Michael Jackson' was generating 80,000 tweets per hour.
This article was first published on brandrepublic.com