Silithus is still one of my favourite zones, similar to why I like Uldum – sand, colossal structures and the epic world event when the gates of AQ first opened. I still have fond memories of the ongoing raid to take down the Emissary outside Cenarian Hold.
One of my all-time game highlights would have to be when I first joined the raid to go into AQ20 (seems at the time they had only done a couple of pulls at that stage) and was asked to do the remaining pulls on my Hunter. It helps when you know the raid leader :P
The zone used to be a major quest/reputation hub in vanilla. There were numerous quests to increase your Cenarian reputation with three versions of summonable mini-bosses, hand-ins and numerous rewards.
It was also one of the locations needed to complete The Scepter of the Shifting Sands, something I was excited to complete.
Players travel to The Crystal Vale in northern Silithus to complete the final quest for Thunderfury, Blessed Blade of the Windseeker.