EVE is probably my favorite MMO of all time.  But it's scale and depth becomes comparable to a megastructure construction project... It's a lot to get going, and once it stops, it's harder to get it going again.  I blame the time based training, as one will be guaranteed to always have less training time than those who have never taken a break from the game.

Regardless, I'm excited to hear CCP is working on a new project.  Hopefully they apply all their lessons learned this far and give us an MMO for contemporary gamers.