Listen to a gem versus an FSSM gem - which one is better?

Just read the sass changelog and find out that the FSSM (a gem used for compass monitoring) has been replaced by Listen

I tried to find the reason, but I can not find the reason. To date, the number of total downloads is FSSMgreater than that of Listen. Also, as far as I can understand (correct me if I am wrong) FSSM gracefully degrades for polling if inotify events are not supported. Listen does not happen.

So, can anyone explain what are the reasons for using the Listen bug instead of FSSM if I want to use file system events in my script?

UPD:  Ha-ha, after updating FSSM and trying to call it, I get the following message from FSSM:

Dear developers using FSSM in your projects, FSSM is almost dead at the moment. Further development will take place in the new joint guard / listening project. please let us know if you need help! ^ _ ^ B - Travis Tilly

So this seems like a decision by the creators of FSSM. This, however, does not negate my question - what happened to FSSM?