I think its safe to say the ones who are successful will be of similar profile to BA's cadets, regardless of the minimum educational requirement. So anyone who has just the bare minimum or your bog standard A level's don't think you will be flying a A330 anytime soon.
Its a very clever marketing ploy by Virgin, by putting the requirements so low they have attracted a lot of media attention which is free publicity. The negative is that they have had every Tom Dick and Harry applying for it thus crashing the website, but still Branson never misses a trick, it's great publicity.