Wilshere, 19, attracted widespread praise after his performances for Arsenal against Barcelona in the Champions League, and he has now made two senior appearances for England.
Capello has already hailed Wilshere as a future England captain and, when asked if he was now first-choice for his country, said: "Yes, yes, because he is good, because he plays without fear, and with confidence.
"Also for someone so young, he is a leader. It is incredible. I never saw someone so young be a leader on the pitch. It is incredible.
"Wilshere, after the game against Barcelona, he has arrived. He has arrived. You can understand the value of that sort of performance. As a young player, I think he is at the top, not only in England but Europe and the world."
Capello has also been boosted by the emergence of Chris Smalling at Manchester United. The centre back, who moved to Old Trafford in the summer, was playing for Maidstone United as recently as 2008 but has been a regular in the Premier League and Champions League in recent weeks.
"Smalling is a very interesting player," he said. "I am monitoring him. I spoke with Sir Alex (Ferguson) and he told me he needs more games, more experience but I think, when you play Champions League games, it is really important."
Capello has a number of key players absent for the upcoming Euro 2012 qualifier against Wales and friendly with Ghana but is hopeful Manchester City winger Adam Johnson and Liverpool striker Andy Carroll will be fit to play a part.
"I just read that Adam Johnson played 10 to 20 minutes on Thursday [against Dinamo Kiev]. I don't know if it is too soon for him [to be selected]. We will see how he goes on Sunday.
"I went to Liverpool to monitor Andy Carroll. He has played just one game [since being fit]. We need to wait until after the weekend games. He is fit but he needs to play games because, every time, the big players need more games to find the good form.
"The squad will be 25 players for these two games. Two players more than normal."