The test realms
haven't been up for long, but Naxxramas bug fixes
are already starting to show up. Also, to help testers, a vendor has been added to Naxxramas that will offer free repairs, free resurrection sickness removal, spell reagents, tome of tranquilizing shot, and rogue poisons. So if you're interested in checking out Naxxramas, it's been easier. However, character transfers to the test realm still seem to be down, so if you didn't copy a character when the PTRs were first brought online, you're going to have to wait a while.