In general IQ scores will be slightly lower for newer revisions of the same test. It's called the Flynn effect, and there is an ongoing discussion in the field about the explanation for it. On face value, it would suggest that people are actually getting smarter over time, but more likely it has to do with what constitutes common experience and how that changes from decade to decade.
As to cutoffs for giftedness, that is also a subject for ongoing discussion in the field. There are some who hold to 130+ (e.g., Mensa), while others, looking at it from a more psychometric view, rather than a membership perspective, have proposed that the cutoff be as low as 120 (all these scores are assumed to be mean = 100, and standard deviation = 15; the cutoffs would be different with different standard deviations). Some practitioners/school systems consider a score at or above the cutoff to be relevant for classification only if it is the global (Full Scale IQ) score, while others would accept one of the Index scores, or the General Ability Index (which combines the measures with more high-level thinking and reasoning on them, and excludes the cognitive proficiency scales - working memory and processing speed).
In any case, cognitive scores below the age of about eight or nine are notoriously unstable. I wouldn't sweat WPPSI scores too much; wait until the child is nine, and test with the WISC-V (out this September).
