From what I've read on the official forums, the daily fishing quests are still sometimes bugged - as they were on the Public Test Realm: When trying to fish for the daily quest fish, the loot window comes up empty. This does not happen for every daily quest. I believe that if you continue to catch nothing, eventually the quest fish will appear. Keep in mind that daily quest fish are no longer always caught on first catch - it might take many catches, as it did originally in patch 2.4.
There's also a post about Crocolisks in the City kicking a character out of the game when recalling to Dalaran, which I know nothing about.
If anyone else has more information, please post below.