This new ruling allowing third year students to sit for the bar - on an experimental basis - may better facilitate the ability of graduates to hit the ground running. What it will do for their mental health is an entirely different matter. I recall that when I was in law school, Georgia permitted 3L's to sit as well.
I imagine some students will push for Arizona law schools to offer a full-on, in-house credited bar review so that students can make bar preparation an on-load activity rather than a second job. I also imagine faculty in other 3L courses will have to adjust expectations about class prep for those first weeks of the spring term.
Update: As ASU Law Dean Doug Sylvester pointed out to me, the rule actually contemplates a degree of protection for this hearty 3L's. Students taking the bar in their third year must have completed all but 8 credits for graduation and may not take more than 2 semester credits during January or February. In addition, the school must certify the student is "academically prepared for early testing" - whatever that means. I'll be curious to see how schools navigate the two credit rule. Presumably students will take short courses starting in March to fill out their remaining credit requirements.