After seeing his side ruthlessly seize the initiative to score three unanswered tries while Wales full back Leigh Halfpenny was cooling his heels in the sin bin, Deans saw enough to suggest Wales will prove a tough proposition in next year's championship.
"They play a great brand of football and have a lot of young talent coming through," he said. "Wales play an exciting brand of football so I see no reason why they can't win the Six Nations."
Deans then on to praise Shane Williams as a "once in a generation player" after the Ospreys winger claimed the 58th try of his 87-Test career when he sprinted over in the dying seconds of Australia's 24-18 win at the Millennium Stadium.
"It was a nice way for him to finish, though I wasn't excited at the time!" said Deans.
"But then I saw who it was and he deserved that moment. Shane is a once in a generation player, see what he's achieved in the game. He deserves every acknowledgement that he gets.
"Shane's a quality bloke and it's great to see his family out there enjoying the moment. He's been a credit to the game of rugby and hopefully our guys at the front end of their careers have the good fortune to play as long as Shane has.
"He leaves a legacy that a lot of players will aspire to in Welsh rugby. It's good for the game and we wish him well."