Even if I agree with the motivation, that of checking code, you're faced with a logistical problem. If the SDK takes off, and a lot of apps are created, then there are going to be more Apps than QA engineers at apple. Then who are they going to give their time to - the money making ones, or the free ones?
What are they going to do if code comes along that conflicts with their business interests? a phone-based iToner for example, or a skype client, or mobile adium. What happens if someone writes a remote for the appleTV while they have one in development?