"He is also the kind of person who, when he sets himself something, he will achieve it. With David Beckham, the only thing you would wish for is that he was younger.
"Will he be part of my plans? You never know. I will have to make choices. I believe basically that Beckham's behaviour will be important.
"However, there is still over a month to the first game (a friendly against Switzerland on February 6) so there is plenty of time for these important decisions to be made."
Capello would also make no assurances on whether John Terry would remain as captain - a role he was given by McClaren after Beckham resigned from the role after the 2006 World Cup.
There have been reports that some members of the Football Association board have been unhappy at Terry's aggressive behaviour towards referees when disputing decisions.
Capello said: "I have just arrived here and there are many things I have to think about. Give me some time.
"I have got over a month before the players meet up for the first game and I will make my decisions."