User blog comment:ClariS/Unofficial PBE Patch Notes (1.0.0151)/@comment-4947142-20121102130608/@comment-4677525-20121102150350

It has to do with the way they are fixing the skillshot bug (where skillshots would have difficulty hitting at point blank/close ranges). It now takes into account the model size of the targeted champion (rather than hitting the center of the target's model) so that it will properly match the visuals. As a result, they've had to lower the ranges on a few of the skillshots so that they aren't longer than intended.

It should be pretty much exactly the same as it is on Live except more consistant at close range, these are not actually nerfs.