1) Ad blocker usage doubles on the desktop in Western Europe and the US by the end of the year.
2) Websites locking out users of ad blockers becomes routine, rather than exceptional.
3) There will be at least one successful legislative attempt to outlaw ad blocking, in Europe.
4) Long shot: Apple ships a minor (+0.1) update to iOS with ad blocking enabled by default. (Blackberry might do the same, but it would not be as consequential as Apple doing it.)
Bookmark so you can all laugh at how wrong I was!