Last month they started Sesame Street Catalog and put out some new compilations (with no previously-unreleased tracks), I wonder if they're just re-naming that or if this is a completely different thing (the press release does mention those albums that were just recently released).
One thing mentioned in the press released is an "All-Times Favorites", I feel like it said that would be a series of albums (like the recent "letters" series), as opposed to a single "Sesame Street All-Time Favorites". I wonder how they'll go about it, I assume character-based ("Elmo's All-Time Favorites", "Bert and Ernie's All-Time Favorites", etc.), but it would be great if they could put out albums focusing on decades (though would they leave out 1969 and do "1970s All-Time Favorites" and so on?). I'd like to see an "Old School Secondary Cast All-Time Favorites" focusing on songs from characters who don't have a particularly big back catalog of songs.