Vidic revealed he would be leaving Old Trafford after more than eight years earlier this year.
Inter Milan have now confirmed that he has signed a pre-contract agreement with them and will move to Italy in the summer.
There are also doubts about the long-term futures of fellow defenders Rio Ferdinand and Patrice Evra.
Moyes insists that Vidic's move will not affect the captaincy but said he is now keen to see what younger defenders Phil Jones, Chris Smalling and Jonny Evans can do in the final weeks of the season.
He said: "It doesn't change but we've got a few more games to go before the end of the season and I've got some young centre-halves I want to see.
"I want them to show me what they're capable of and I'll be looking to introduce them in the last month or two."
Moyes has been critical of the coverage of an online petition demanding that Tom Cleverley is not involved in the England squad for this summer's World Cup in Brazil.
The 24-year-old midfielder has been criticised for his performances for club and country this season.
But Moyes has been angered that a social media petition has been flagged up.
He added: "I'm surprised that the media would pick up on something on social media and make a big case of it because I think that's wrong if that's the way it's come about in the first place.
"Tom Cleverley is a fantastic young player who is developing all the time, he's a great trainer and he's first out and does his best every day in training
He never gives it less than that.
"That's why Tom will succeed and that's why I'm surprised it's been picked up on."
United have had to wait a week and a half for a match following their 2-0 Champions League defeat at Olympiakos.
Moyes admits there have been positives and negatives to the break and he has been eager for the chance to put right the failings in Athens.
He said: "It's allowed some players to get games
Darren Fletcher got a game for Scotland, Chicharito, Shinji Kagawa, people that have not featured as much as they or we would like.
"But it's also been a hindrance because we were off the back off a bad performance and a bad result at Olympiakos and we wanted to put that right much sooner but the way the league and the fixtures had worked out we didn't have a game."
With United in seventh place and 12 points off the Champions League places ahead of the trip to West Brom, Moyes has written a letter to season-ticket holders thanking them for their support.
He believes the United fans have made a tough campaign easier to endure.
Moyes said: "The club is built on a fantastic supporter base throughout the world not just here in Manchester
Manchester United are supported everywhere.
"I saw that when I went on tour and more importantly I'm seeing it a lot at Old Trafford
I'm seeing it a lot and the supporters understand the difficult period we're in and they're really backing the players.
"If you're a football supporter you understand what loyalty is so if you follow a football club passionately you follow them whether it's doing badly or doing well and sometimes it takes stronger supporters to support the club when it's not going well.
"It's easier when you're winning and I think at the moment the Manchester United supporters realise there are some changes taking place and that their time will come again."
Source : AFP
Source: AFP