Fan Graphs question

I was looking at Jay Bruce's fan graphs page and noticed something odd.

If you go down to 'Plate discipline' http://www.fangraphs.com/statss.aspx...n=OF#pitchtype, you'll notice that Jay has made a pretty big leap with making contact with pitches outside of the strike zone (O-contact%).

But that's not my question. If you click on 'show averages,' there was a pretty big leap from 2009 to last year and this year.

My question is, has umpiring changed? Is it more inconsistent? Has pitching become that dominant that guys are swinging more 'outside the zone?' Am I just reading too much into this? No big deal?

My guess off the top of my head is that Jay is hitting breaking balls better that start in the strike zone but then move off the plate.