This was definitely the least smooth launch I've ever had, simply because I wasn't even able to log on. After finishing my daily errands, I logged on at about 11 pm my time, two hours prior to launch. At lauch I lagged like mad, just like everyone else, got stuck on a loading screen, was teleported to Shrine, had no portals, flew to the Stormwind portal in Paw'don, was stuck on a loading screen and got disconnected. After that I spent about an hour trying to log on to no avail, while the friends I was on Skype were managed to get a good amount of quests done in Draenor. So not everyone had a rough launch. I'm perfectly fine with lagging in game at launch, it's just a part of it... But it was a little disappointing I didn't get to experience so much of that rush this time, the madness of trying to tag mobs before anyone else's finger could tap their key. Or being stuck in a huge swarm of helicopters, like in Pandaria, which seemed like a very smooth launch at first.
I'm not complaining, though. So far Warlords of Draenor seems like a very good expansion, and the questing was made perfect. No question about that - from me anyway. I love that you don't spend ages questing in the same place in an area, but do a couple of quests here and then move there. It is the perfect style of questing for me, and I love it, as well as the "events." I am not level 100 yet, although I stayed up for over 24 hours on the day of the launch. Or maybe that is why, since my leveling efficiency wasn't very high a few hours into the expansion.
Well, what kind of a launch did you have? Have you been present at any other WoW launch?