I just saw it on You Tube that's why I'm posting now so sorry in advance for bumping an old thread.
Though as for my thoughts on the special, I thought it was very good. Some times I forget that SS takes place in New York so the fact that they met people from different cultures in different neighborhoods was very interesting. I do agree it could have used more Muppets like Bert, Ernie, Snuffy, etc. Sure we saw them in pictures at the end, but not the actual characters.
As for the recasting of Big Bird, I'm on the fence. I do agree that Matt's version of the character doesn't sound like Carroll's (heck, Carroll's most recent versions of Big Bird and Oscar don't sound like Carroll's now either as someone mentioned, but that's another story.) Anyway, Matt's Big Bird doesn't bother me too much anymore. I guess I gradually got used to Matt as Big Bird from when they had "Journey to Ernie" and his other performances of the character over the years. With Oscar, it's kind of a different story because Eric hadn't been performing him as often over the years, but within time I'm getting more used to that as well.
Anyway, just wanted to put in my two cents on this.
Also, this isn't the first time Carroll didn't perform his characters in a "Sesame Street" special. One example I remember was that "Sesame Street 4D from a few years back. I think Matt was BB and John Tartia-whatshisname was Oscar. So I thought I'd mention that one as well.
So with that said, there's still a chance Carroll will probably come back to perform his characters on occasion. You never know.