Playing the famous Web entrepreneur Sean Parker in “The Social Network” has apparently gone to Justin Timberlake’s head.

The singer-turned-actor, who is currently appearing opposite Clint Eastwood in “Trouble With the Curve,” has been working hard on a reboot of Myspace, the once-dominant social network that has since become a cautionary tale for the fickle ecosphere of the Internet.

Timberlake, who became part owner of Myspace last year, tweeted a video demo of the site’s new design and interface. Following a simple intro declaring “This Is Myspace” in a modern font, the demo takes us through a mock profile where easily accessible music and video selections appear in seamless tandem with user photos and comments, all comingling in what looks like a marriage between Facebook simplicity and Apple aesthetics.

The sleek, clutter-free interface is light years away from the wonky, all-too-customizable Myspace of yesteryear, where users could insert HTML code to make their pages look almost any way they wanted -- bringing an ultimately disjointed user experience to the site.

In addition to the demo, a message appeared on Myspace stating, “We're hard at work building the new Myspace, entirely from scratch.”

There was no immediate word of a launch date for the new site, but those interested in joining can leave an email contact and “expect an invite soon.”

Myspace, which was launched in 2003 as a platform for bands and musicians, is returning to those roots, “empowering people to express themselves however they want,” the message said. The new site will also have a heavy reliance on TV and entertainment.

Last year, News Corp. (Nasdaq: NWS) sold Myspace to California-based company Specific Media for $35 million in cash and stock, the Los Angeles Times reported. At the time, Timberlake took on an ownership role, and his celebrity status has brought a desperately needed sense of glamour to the creaky site.

Rupert Murdoch’s conglomerate had bought Myspace for $580 million in 2005, when the social network was at its peak and Facebook (Nasdaq: FB) was still just a small niche network for college students.

But fortunes changed quickly for the two sites, with the latter rising to its current level of almost a billion users while Myspace plummeted out of the mainstream eye. At the time, some saw its News Corp. ownership as a violation of social-networking’s democratic principles, while others complained that the site had become too unwieldy and advertising-heaving in contrast to easy-on-the-eyes Facebook.

Whether or not the new Myspace can hope to overcome that baggage remains to be seen, but its new direction comes at a time when Facebook is under pressure at almost every front. Its perpetually tumbling stock took another hit on Monday after a Barron’s reporter called it “still too pricey.” Meanwhile, the site continues to come under fire from privacy experts and users, many of whom simply don’t trust that their information is secure on Facebook, according to recent polls.

According to the traffic tracker Alexa, Myspace currently ranks 187 out of all the websites in the world. Earlier this month, as was reported on several tech and news blogs, Facebook surpassed Google to become the top-ranked website in the world. As such, the new Myspace will clearly have some catching up to do when it launches. But on the Web, anything is possible.

Just ask the old Myspace.