A new year, a new you: even if you're an 80-year-old media magnate, it appears the transformative allure of 1 January can prove irresistible.

Rupert Murdoch, the chairman and CEO of News Corporation – who may have more reason than usual to want to make a break with 2011 – has apparently joined Twitter.

Users of the microblogging site have reacted with a mixture of incredulity and unabashed horror to a declaration by its executive chairman Jack Dorsey that Murdoch had set up a verified account and would be gracing the site with his unique observations. "With his own voice, in his own way, @RupertMurdoch is now on Twitter," wrote Dorsey.

Within hours, the media tycoon had amassed more than 14,000 followers and was giving them his views on everything from the US presidential election to his family holiday in the Caribbean.

A cursory glance at his output reveals that he considers Steve Jobs's biography to be "interesting but unfair", that thoughts are best kept private in St Barths ("like London!"), and that George Clooney deserves an Oscar for his performance in The Descendants (whose distributor is News Corp-owned Fox Searchlight Pictures).

Murdoch's latest tweet, posted late on New Year's Eve and betraying a certain technological unease with punctuation, reads: "Huge NY eve do. Oligarchs and silicon valley biggies(like Jack) . May. Learn something".

The arrival on Twitter of one of society's most divisive figures was welcomed by some, but pilloried by many others. Piers Morgan, former editor of the News of the World, wrote: "Now this is going to be fascinating … welcome to Twitter my old boss @RupertMurdoch."

But the former deputy prime minister John Prescott captured the reaction of many when he made indirect reference to the phone-hacking scandal which saw Murdoch come under huge pressure in 2011. "Welcome to Twitter … @rupertmurdoch," he wrote. "I've left you a Happy New Year message on my voicemail!"

Another tweet suggested Murdoch follow Tom Watson, the Labour MP whose dogged pursuit of the scandal has won him many fans.

Despite a blue and white tick appearing next to the Murdoch account – the sign Twitter uses to show that an account has been "verified" as belonging to the right person – many remained dubious as to its authenticity.

Michael Wolff, a contributing editor of Vanity Fair and biographer of Murdoch, declared the account to be "fake, fake". Another user, @factor50, commented: "It can't be him, because all he should be tweeting is SORRY in every single breath." But Dorsey's tweet seems to prove the doubters wrong.