Not really. WoW broke the mold in a lot of ways. One if those ways was the markets it expanded and the millions of new-to-the-genre players it brought in. Before that (and even during Classic) the majority of MMO players simply transplanted from one game to the next. From Ultima to Everquest, from Everquest to Star Wars Galaxies, etc. Personally, I played City of Heroes as my first MMO and then came to WoW. There are very specific aspects of the genre that people find the appealing and they're things you can't get with a console game.

Its no different than people going from racing game to racing game or night club to night club. Assuming that people treat it like a job is presumptuous, but assuming that they'll continue doing something they enjoy with a different franchise is not.

@Feniks

Your comment was dead on for me.

I started out my RPG experiences with Ultima: Exodus on NES. I eventually moved on to anything from Black Isle Studios and keeping up with the Ultima releases until UO (Ultima Online) was announced. I applied for the alpha but ended up getting in on the beta and have been hooked on MMO's ever since. I went from MMO to MMO for a long time and each MMO has a particular appeal. I went to Everquest because the gameplay in UO went nowhere and I wanted to try a leveling MMO. I went to SW:G because it was Star Wars (why else?). I went to EQ2 because housing killed SW:G and I had fallen way behind in EQ's expansions.

Originally when WoW was released I didn't even want to try it. The graphics style for the warcraft series had always been too cartoon-like for my tastes and I enjoyed the realism of other games. Once I tried a trial of WoW the gameplay hooked me and had me buying the game before the trial was up.

Since coming to Wow in 2006 I have tried dozens of other MMOs. They run a sale or put out a trial and figure there is no harm in trying another game. D&D Online, Lord of the Rings Online, Warhammer Online, Matrix Online...

The only game I would have ever considered leaving WoW for and restarting completely was Warhammer Online. I did leave for a while and the game was great; but the player base went up in smoke after the first month or so and I ended up soloing through everything on a 2nd character (not fun).

Games I'm looking forward to? Warhammer 40k, TRON: Legacy, 'Copernicus' from 38 Studios (I'm a huge fan of Salvatore)