They're releasing it just as fast as WoW does and you don't see WoW losing 98% of it's raiders. 'Raiders' that jump ship so easily will jump ship to a different game every month and there's no way they could keep up with the content they demand.
WoW isn't losing 98% of its raiders because WoW raids are much more challenging and you actually have to do them to get the best gear. In SWTOR, you do not have to complete a single tier 2 operation to get black hole gear, and it is fairly time efficient to get enough comms to gear yourself up in black hole. Dread Guard gear is the slightest upgrade over black hole, and theoretically if you have enough credits, you can buy all of the BiS gear. When you don't have to do any high-tier operations to get great gear, much less people commit to doing them. When less people want to raid, developers concentrate on other things in expense of the raid content.
Of course, raiding is supposed to be more for fun and not for gear, but since SWTOR is courting casual players more than "hardcore" players now (or even more so now, they always favored casual players), the casual players will dictate the future of the game, meaning the rather easy raid content, low class difficulty, and buffing of popular classes (marauder *cough *cough) will continue.