GAH, it's been quite a while since I've posted on Smogon, but this datamining info is too interesting for me not to get involved in this discussion!
(No spoilers in this post by the way)
Frankly, what I'm most surprised about is that Game Freak allowed this to happen. Everything from the Hoopa to the Mega Latios/Latias leaks should have proven to them that we are very curious fans with ways to find hidden data. I just thought they would have learned their lesson by this point and taken anything too revealing out.
A simple rule of thumb is that if you don't want people to datamine your game, don't include stuff that's interesting enough to datamine.