Usually when I take a break from WoW, I don't play anything and I focus on other things. This time however, I wanted to quit for good and play other games. Let's just say, in doing that, I learned how great and well developed this game actually is.
Games I Tried: (Found a lot of them through online best MMO lists)
Age of Conan
Command and Conquer (Old school.. up to Generals)
DC Universe Online
Dungeons and Dragons Online
Path of Exile
Runes of Magic
Star Trek Online
Now, while some of these (and I mean only a few of them) were fun to play at first and had their own little quirks that made them fun, they just don't compare up to WoW. They don't match up in terms of options, features or gameplay. The only thing that some of these games has over WoW is the environments look realistic but truth be told, it looks weird. The gameplay looks weird when you have realistic looking environments and flashy spells everywhere (it just doesn't work for me).
I will say, the most frustrating game I played hands down was without a doubt League of Legends. This game was beyond frustrating to me... Every game pretty much boiled down to this:
People arguing before the game starts about who's going what role
People arguing about other people's builds, name-calling, etc
People complaining to their jungler because they're not at three places at once
The list goes on and on but this is by far the worst community of people I had ever met. The people were such try hards, it was frustrating. If you think the 300k DPS in LFR linking the meters every pull is a try hard, I urge you to try out LoL and that guy won't seem so bad.
WoW is pretty damn polished up and well developed compared to pretty much every game I tried out there.
I know a lot of people think Blizzard doesn't listen to the community but oh boy... they listen a lot better than the games I tried. The only game I found with a great development team that care was Path of Exile and I wasn't into it.
Path of Exile is a decent game for the budget it was made on but there are Kripp fanboys ravaging that game... that community was pretty good before his fans got a hold of it. When Kripp isn't streaming, they go into every other stream marked PoE and just tear apart the streamer, what their build is, etc. I thought Sodapoppin by far had the worst fanbase but Kripp's definitely sets them apart.
TLR - WoW is a great game once you take some time away from the game and realize how poorly most other MMOs and online games are made. Plus, the community is FAR better than say.. LoL. WoW's pretty good and WoD looks amazing so far from what we've seen.