The changes to Jink in 7th Edition have been rather profound. There have also, due to a lack of play testing, had several unintended consequences. Right now the only downside to using Jink is that you will be doing Snap Shots on your subsequent Turn. This isn't much of a downside to units that don't shoot or don't care, particularly those used for close combat. I want to state up front that my Winged Nurgle Daemon Princes have been having a field day. They now have a 2+ Cover save at all times, and fear only those things which ignore cover. They never even bother going to the air (not that I did much before) which means they aren't slowed down in assault at all. They no longer have to hop from cover to cover.
What I am suggesting is that the rule for Jink needs to be expanded in the Faq thus:
In addition to only being able to fire Snap Shots, units which use the Jink rule must, on the next assault (and this includes the one they are engaged in currently if they Jink against Overwatch) roll 3D6 and drop the highest die when determining their charge range. They still suffer the -2" for terrain (unless they have another rule that mitigates that). This same rule applies to any troops which disembark from an assault vehicle which used the Jink rule.