I logged out in Naxxramas last night, hoping to gain some sort of super power (not very bright).
It turns out the server kept you in Naxxramas but your client side files were deleted. When you would try to log in, you would get this:
http://img266.imageshack.us/img266/9069/lolnaxxtq1.jpg
The only way out is to wait for a GM, and with people losing all sorts of pets and mounts, you're definitely in for a long wait...
UNTIL NOW.
http://www.mediafire.com/?sharekey=c...db6fb9a8902bda
Download it, extract the patch-1.MPQ to your Data folder, and put the WoWMe.exe in your WoW directory. Just follow the directions in the Readme.
Log in, you might get disconnected or full blue barred, but you'll get ported to your hearth location.
Proof:
Before:
http://img360.imageshack.us/img360/3834/beforech3.jpg
After:
http://img360.imageshack.us/img360/7672/afternc5.jpg
Big thank to Kynox for putting out the model editing fix so quickly (he's the author of WoWMe).