I'm curious to see how the blocking of slow-loading trackers will affect browsing ability. I put a pi-hole on my network and have found that some sites become extraordinarily slow to load (like more than 20x as slow as without the pi-hole), presumably because there's something being blocked that prevents the rest of the site from being loaded. Needless to say, this makes the pi-hole a win-some-lose-some proposition.

Hopefully Firefox's implementation will avoid this pitfall!