[Resolved with RIFT 2.8 Hotfix #2]
There’s been some recent crashes on various shards and even cluster-wide crashes. Trion has decided to turn off the Auction House temporarily to hopefully reduce the chance of these crashes occuring.
Fix is being worked on.
Here’s a quote from Daglar about the crashes:
Hey folks,
Just wanted to hop on and give an update about the recent sporadic crashes. We’ve got several potential fixes for these issues going into a build right now. The cluster level crash is a result of the server level crash passing off some bad data – and cluster level crashes are certainly bad news.
We are going to try to get this into QA and potentially deploy tomorrow. Weekend deploys are not what we like to do, but the number of crashes has slowly increased as we’ve gone into prime time.
We’ll get messaging out as soon as we can if we are able to get something out tomorrow.
Sorry for the inconvenience everyone.
Update – 8:40 PM PST – We’ll be completely turning off all features of the auction house until we can deploy a hotfix. We strongly believe that this action will remove the edge case that causes the current crash.
You can check out the thread here.
RiftGrate 
there was a update this morning
Update – 11:15 AM PST – QA has been reviewing the build. Still more to verify. Looks very likely that we will deploy today. Rough estimate would be 1:00 PM PST for NA if all goes according to plan.
Thanks for the info Chris! Looks like Hotfix #2 brought it all back up!