E.B.
When talking about percentiles an easy way to think about them is this...Out of 100 children, your son scored better than ___ (insert number here) of them. So if his percentile was 99, it would be "Out of 100 children, your son scored better than 99 of them". This is how we explain percentiles to parents at school (I am a speech therapist). The gifted score of 130 you read about is probably a standard score - were there any of those listed anywhere? Either way, sounds like your son is doing well.