[potatolicious]

Neither? The address book debacle was a big deal for a little while, but the bad press faded quickly.

I also don't think Facebook's position is unchallengeable. After all, Facebook wasn't the first social network, and it looks like the youth today aren't using Facebook nearly as much as older generations, preferring newer apps like Snapchat.

In all likelihood Path destroyed itself by being a not-very-good Facebook competitor. This says little about the feasibility of toppling Facebook.