Looks like the groups bug still exists. I have Adium 1.4 with Skype 2.8.0.851 and the 8Nov (11/07/2010) Skype Plugin and the Skype group recreates itself every time I close out both Adium and Skype and restart Adium. When Adium restarts, it recreates the Skype group.
I have the following set for Skype account options:
Auto-start Skype if not running
Make Skype online/offline when going online/offline
# by 07BladeRider on 11/15/10 at 17:55:43
I have the following set for Skype account options:
Auto-start Skype if not running
Make Skype online/offline when going online/offline
Connect when Adium opens