I feel that Adblock is a serious threat to Facebook. If it gets the viral traction, imagine half of the Facebook users using Adblock. The result would be disastrous.

I use Adblock and love it dearly. I don't have to watch annoying ads on youtube or deal with intrusive banner ads suggesting I a guide on how to make $5000/day at home in an instant.

I do sometimes want to see ads, and that's when I google something and I want to actually see the advertisements. This is a good sign for google although overall, adblock will slowly cannibalize their ads