At just 26 years old, the relatively unknown actor will be the youngest to ever take on the coveted role of the Time Lord. And he will have big sneakers to fill following the acclaimed David Tennant, who late last year announced he would be stepping down.
Many Who aficionados now consider him the definitive Doctor.
This year in the UK there will be four Who specials with Tennant, expected to depart early next year.
"As soon as Matt walked through the door and blew us away with a bold and brand new take on the Time Lord, we knew we had our man," said new producer Steven Moffat. "2010 is a long time away but rest assured the Eleventh Doctor is coming -- and the universe has never been so safe."
Australian viewers can currently see Smith in the BBC drama Party Animals, screening Tuesday nights on the ABC. He has also appeared in BBC drama The Street, and Ruby in The Smoke alongside Billie Piper.
An excited Smith said, "I'm flabbergasted, haven't slept really, to be honest.
"It's sort of an iconic part of our culture. My grandfather knows about it, my dad knows about it. We've been watching it since 1963. It has the iconic status that Robin Hood or Sherlock Holmes (has).... and I'm taking that on. It's my responsibility. It's nerve wracking. Exciting!"
True to the secrecy associated with the role, Smith won the role over Christmas but had to keep quiet until the public announcement last weekend.
"When I got the role I paced around the room for about three days because I didn't know what to do," he said.
"I was just smiling and thought 'I'm the Doctor!' It's weird."
Meanwhile there is more good news for Aussie Who fans with ABC planning to screen the 2008 Christmas Special this month, instead of having to wait longer, which is usually the norm.
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