Hmm.
I haven't tried port forwarding yet, and I have the same problem.
I tried something quite funny, though.
There was some console command, which I will add in as an edit of the post, which allows you to see the join server list.
My ping was dead, but I tried to join my own server, WHILE I WAS IN MY SERVER.
Console is here:
Connecting to "Katadeus' Weapon_ModRocket (Beta)" (216.246.154.209:28000, ---ms)
Download Sounds: True
Download Music: True
Download Textures: True
Download Projectiles: False
Download Items: True
Download Debris: False
Download Explosions: False
Then crash.
But in actual console, there was also an error message, which did not show up in the console text document.
Also, while looking through the console, I found a TYPO.
Auth Continue Successfull: Katadeus
So, yeah.