Preview is a better term to use. I think everyone reacts negatively when someone brings up that it's a preview because of the fact that MS said this is the same final build. As with previous experience from other betas i've been part of (NXE, Kinect beta), not all bugs get ironed out once the final release is out, especially for an overhaul of this magnitude.
Yes, some of us are getting issues (music app, games app among other things), but so long as we get the feedback out there, i'm sure MS will work on it before the rest get it. I like to think of it as us helping to make sure the rest of the population not in the preview gets a better final product.