From what I've heard, they are gradually being put to the cutter's torch; however, some interest has been shown recently by a few organisations in purchasing and restoring a CV880 and CV990. The aircraft are somewhat dilapidated, but are mostly intact.
Part of the reason they have been sitting there for so long is that at various times, they have been considered as potential freighters. Some conversions have been made, but nothing really ever came to fruition in this venture. Now, the aircraft are no longer allowed to fly because of their high pollution and noise.
The only concrete example of one of these types in flying condition is in El Paso; it is a CV990 which is run up and taxied frequently, and is being sought after for ownership by an aviation enthusiast's club. Hopefully, the same will come to pass for a CV880 before it's too late.