I usually don't EV train. The last time I've trained any of my Pokémon for EVs was in Platinum, if I remember correctly. Some people may find EV training to be simple, but to me, it's quite complicated. Plus, it takes you a lot of time, energy, and motivation, which I simply don't have. D:
I don't know if I'll be EV training or not in my Pokémon Y version, but if I do, it'll most likely be when I'm finished with the story and start to build a proper team for myself. Also, if the rumor about Super Training is true and it does, in fact, increase your effort values, then I may do that instead of going through the old-fashioned EV training method—it's such a hassle!