ffxi had multiples of each type. so whats the problem? we had like 4 healers, 3 tanks, several dd. and a few of those are hybrids of healer/ dd.

WoW does the same each class has several different roles to fill based on what tree you used.

classes will always have multiple roles. like dcuo each class as a dd style and either tank, healer or controler style. (based on what power you picked.)

Personally i wouls much rather look for other players then certain classes. This will make forming parties easyer and less likely hood of "job of the week". I don't wanna sit and wait fir hours like in ffxi because there was no pld around our whm. playing rdm got hard as I liked to melee and i just happen to be the only rdm around. PPl wasn't pleased with me.