We will be making changes to directory permissions tomorrow which will limit the ability of users to list the contents of some directories. You will be able to change directory through them, but you will not be able to list the contents.
This will for example affect users connecting via FTP to upload files – you can go to the directory you own, but you will not be able to list all the directories one level up. This is a cosmetic change, you can still get to the directory, but you must know its name.
If you have any questions after this change is made, please post to news://news.sonic.net/sonic.os.unix