Yeah, it was a nice feature... sorry. That was noted in the staff discussion about the change, but there wasn't enough support to keep it in.
Basically a bunch of people couldn't figure out how to use quick edit, and didn't realize they could edit thread titles by clicking "go advanced", so on the balance, disabling quick edit so the "go advanced" view is the only view probably reduces staff workload.
(the sad smiley is for the loss of the feature; reducing staff workload is a good thing
).