I have a had very brief stint with only two others:

Star Wars Galaxies(not bad, especially if you like star wars)
Ultima Online(nothing compared to WoW)


WoW is by far my favorite and most
played online game ever, thus far.

Ah I knew I forgot one.  Star Wars Galaxies.  You know, the premise of that game isn't bad.  The graphics were super outdated and the physics were terrible.  I remember flying off a cliff with my speeder and not taking damage upon landing.  I also remember the Star Destroyers in low orbit when playing at night.  That was pretty cool.

You're right though.  Nothing beats World of Warcraft.  It's such a good game in my opinion of course. 

I spent 3 years playing and completing everything in Guild Wars before I was talked into giving WoW a go by some IRL mates...I had managed a level 20 of evey character type, and complete all the add ons...but I was looking for something new when my guild started to lose interest, and the majority of them went to Eve waiting for GW:2...Eve didn't interest me much, so I ended up here in WoW...LOL

I am not one of those that will get drawn the argument about this game is better than that game etc...but I have found both games to have their pro's and con's and I have enjoyed and hated experiences at times in both...