It's official Rooney Mara is the new IT girl, having nabbed the hottest role in Hollywood as the Girl with the Dragon Tattoo.

Since the announcement Mara has become a household name in Hollywood and Vanity Fair are said to be planning a cover.

Amazingly folks seem to actually like her--rare for Hollywood.

"She was a sweetheart. She's still new in the Industry, but I can tell she's going to be in this a long time. She kind of reminded me of a Natalie Portman...her energy and everything."

So said Social Network costar Cedric Sanders when he was asked him what it was like working with Rooney Mara

Ironically Natalie Portman was one of the Hollywood ladies said to be plotting to get the role, but she was turned down because she was considered too old.,

Rooney’s Irish resume is pretty substantial. Her grandfather is Timothy Rooney, the proprietor of Yonkers Raceway in New York and the 2005 grand marshal of the New York St. Patrick’s Day Parade. Timothy’s daughter, Kathleen, is Rooney’s mom.

Patricia Rooney Mara, her real name, is also the grand-niece of Daniel Rooney, currently the U.S. ambassador to Ireland and founder of the global Ireland Funds which have raised millions and millions for Irish charitable causes. And her sister is Kate Mara, an actress who’s appeared in the TV series "24" and "Nip/Tuck".

The Rooney family, of course, founded the Pittsburgh Steelers football team, and their Irish roots run deep. They trace their ancestry to Co. Down, and family members regularly visit the homeland.

Rooney’s football lineage continues on the Mara side as well. Her dad is Chris Mara, whose grandfather, Tim, founded the New York Giants. The legendary late Giants leader Wellington Mara is her grandfather, so it’s assured that as far as football and acting royalty combined, Rooney’s got that niche all sewn up. "F--k that girl," a frequent competitor—for auditions, at least—dished about Rooney. Jokingly (we think). Indeed, we hear Rooney is a sweetie. This other rising actress has just lost way too many roles to be too happy that Mara's going to be a huge box-office star.