Vilanova has made an unbeaten start to life in La Liga, winning seven of his first eight league games in charge.
Cruyff admitted that he has been impressed with Barca's early-season performances but wants to wait to pass judgement on the current coach.
He told the Daily Mail: "Everything is going great for him now, just as we all expected.
"He knew the players, he knows the club very well, he helped Guardiola and was a part of a successful management team. But now is not the time to judge him as a coach.
"The time to judge him is when something goes wrong or when things don't work out, when there is a crisis. That's when you know if the coach is capable."
Barca are on course for for three successive Champions League victories when they host Scottish giants Celtic in midweek.