The design team has said the focus is on frequent group content (read warzones, flashpoints and operations) and infrequent but much larger story content updates. We have seen nothing but group content added all this first year. The soonest story content can come at this point is December. I don't think that is too soon, or at all unfair to the schedule of development for group and endgame content. People are asking for re-play value. New story possibilities provide that.
I'll certainly agree with you on that. Here's how I understand the whole delay.... given a coder and a writer of equal skill, writing code is much easier than writing story. You know what needs to happen and you have a relatively good base idea on how it can happen. While some things need reworking every now and then, it's pretty much a straight path. A story is much more complicated as it requires a lot more imagination. I can understand that, but... I haven't seen a whole lot of story content being added to the game, which makes me think that either they fired all their writers once the game was out (Overall, a pretty bad idea, considering it being a story-driven game) or they have one too many things said writers are working on rather than focusing on single projects to get them out of the way.
Players will always want more, so prioritizing tasks for the writers in an attempt to get content out in a timely fashion should really be done, because honestly, I don't see why there would be a hold-up otherwise.
Disclaimer: I know there's a whole lot of ifs and maybes in this post. It is pretty much me letting my train of thought go. Practically nothing in this post is and can be substantiated by evidence I am able to provide.