The thing about competing with FB is that it’s actually not hard.

(a) performance. Every other attempt has been slow. FB is just email v2. It’s not complicated.
(b) minimum features. Every other attempt has been either too little (I won’t name names), or too pretty (I won’t name names).
(c) confusing twitter (news) with facebook (email). The fact that we don’t have a twitter clone in fb is rather odd to me. The fact that a lot of startups try to make a twitter clones just … amazes me. Retweets are only one measure. Why doesn’t twitter rate users, and conversations on a subject, as well as the popularity of a stream?
(d) confusing medium( articles -I have no idea if that’s gonna survive) with facebook ( conversations on articles).
(e) confusing quora and Wiki: wikipedia is great beecause most of it was fukcing STOLEN from the encyclopedia. The problem is that there is no competition, and no method of showing right, libertarian, and left positions on subjects that need it. For the simple reason that editing is a monopoly (cult) where there IS NO NPOV on most questions OTHER than reciprocity (Which is beyond them)..
(c) Lacking taboos – its one thing to select your interests and friends, its another to select taboos that you don’t want to see that limit what you can see (and say for that matter).

Anyway. The market is there to provide a competitor but the minimum feature set isn’t something you’re going to produce in a few months by hobbyists. That era like the era of single programmer video games, has all but passed except for outliers.

Minimum features. Court the adult market and therefore the money. Rember hat FB makes a disproportionate amount of its money from the third world. That means there is an amazing opportunity for advertising in the first world, at far lower prices, with zero trickery involved.