We'll be covering ALL the extras - including the commentary and other retailer exclusives - in our review at TrekCore. Definitely going to be putting a lot of long hours into this one.
The commentary is not audio-only; there is a bunch of on-screen stuff happening to go with it, and the running time is not the same as the final film. A sync-watch won't help you with this one.
Any hints as to when the review will be up? It would be nice to be able to make an informed decision on if I should cancel my existing preorder and get a different version before the film is released.