So I just got the 12/19/11 patch and...

... now when I load up SK and I'm selecting my knight all I can see is the eyes (which should be covered by a helm) and the "military wide vee" accessory (although that is glitchy, for some reason). The rest of my knight is totally invisible.
Upon seeing this, I hoped that once I selected the profile and began playing it would go back to normal, but this wasn't the case. I loaded up in the Arcade, and everything was glitchy like crazy. My knight was still invisible, save for the "Military Wide Vee," my knight's eyes, and the red glow from where my Dark Thorn Shield should have been on my back.
The ramp going down to the terminals was invisible as well, and underneath I could see the the first platform through that now-empty space. Also, when I inspected another character, all I could see of it was the head (the helm and eyes were fully visible) and a black egg shaped shield with the red letters "ERROR" going across several times. This also occurred on a few surfaces within the Arcade.
To see if I could still adventure, I went to a terminal and tried to join a party in Tier 3, but as soon as the loading process hit 98%, the game stopped responding and I had to close it. I opened it again and it tried reconnecting me to the Tier 3 terminal, but again around 98% it stopped. I gave up and tried to move into the Town Square. I couldn't do that either, once loading hit the high 90's.

Essentially, I can no longer play the game. Now it tries loading me up into the Town Square automatically and it does not work.

Guess I should mention that I also run this game off of Steam, in case that's helpful.
What the heck is going on here, and does anybody else have this problem?