[fela]

I think the best term would have been statistically surprising, because it strongly hint at the fact that the result would be surprising under the null hypothesis, witch really is all that "statistically significant" really means. Sometimes surprising results happen, but all other things being equal they might hint at the null hypothesis being false. I could also live with "statistically interesting". "Detectable", suggested in another comment, seems to have some of the same issues as significant, it is too strong and seems to imply that now we know something is really there.

[vharuck]

By the reasoning behind significance, "surprising" would be a great drop-in. However, in most studies, it would be more surprising if the null hypothesis were true. Statistically significant results are pretty much a given.