I don't *have* the beginner box, but from the previews and discussion there are a couple of things I know or can surmise:
1) Obviously full character creation rules, and the races/careers not featured among the pre-gen characters.
2) The concept of specialisations (kinda like sub-careers). In the full game, talent trees are attached to specialisations, whereas in the beginner box they've been simplifed into your career.
3) Potentially some rules - from another thread it sounds as if the rules for assisting with a check aren't included.
4) I'd assume (but could be wrong) that there isn't a full equipment/vehicle list.
5) In a similar vein, I'd assume the rules for equipment/vehicle modification aren't present.
6) Based on the PCs and adversaries featured, I'd assume there are no rules for the Force (they are based on a specialisation that isn't present among the pre-gens).