I don't expect the beta to be finished at this point Theo. I don't think it's unreasonable to expect there to be a bread crumb quest for the new 85 content though. For the Cata beta, I got in after about two weeks, and they already had the bread crumb quests for the level 80 zones. Hyjal wasn't even close to being complete, but Vash was pretty well done. The beta for MoP has been out for almost two months now. I would think Blizz would recognize that most people who play the game don't like just randomly killing sh*t, so if they want to test out abilities and balance them, the best way to do this is to make sure people know where to go for the new quests.
Expecting a beta to be exactly like the one before when they have a completely new way of getting people into the beta isn't really that smart.
Sure, they could have put breadcrumb quests in to lead you by the hand to the panda that ports you to the conflict zone. But honestly? I can see why they didn't. The developers are obviously
focused on talents and abilities at this point, and they aren't doing the beta for you
. The beta is for them
. They test, figure out mechanics, etc.
This is really like their early closed betas in the past (which being opted into doesn't get you in, you have to be invited by a Blizzard employee specifically), like the WotLK beta I took part in. It's not like the Cata beta or the later stages of the WotLK beta.
Just for reference, they also didn't have breadcrumb quests in WotLK. They didn't for Cata closed beta either.
TL;DR the devs don't care about your experience at this point. They care about the balance they're trying to achieve, then they'll work on your experience.