So I just got OSX 10.6 installed on my Mini 10, using Netbook Installer, no other software installed. Installed steam and tried to login. Received an error message saying steam couldn't connect to servers.
Tried uninstalling/reinstalling steam.
Now I have done some digging around and found that alot of people were having issues with peerguardian causing this, but I don't have peerguardian installed on my system. The interesting thing is when I go to the peerguardian website, it just displayed "It Works!" which leads me to believe that there is some kind of pre-installed software that is acting as a firewall preventing steam from connecting to the servers.