Good thoughts. I'll share a couple that seem to be relevant.
Facebook, for all its faults, has done a masterful job of making it really easy for folks to integrate. And it's a very intuitive interface, even for folks who remember MySpace (though I never cared). Notification of what's happening in relation to your account are instantaneous. Until someone comes up with those things, I doubt it'll be replaced.
Is Steemit going to do all that? I don't know. But I kind of don't want it to. Some of the features would be nice, but maybe trying to be a Fb replacement would be short-selling it.
A downfall right now is that there's a lot of noise, there are a lot of very popular people making huge sums because of their followings, there are a ton of very poor articles and a massive amount of great content not getting attention. How will this flesh out? We'll see. Of course, poor writers usually give up. Hopefully people will wisen up on not cheapen the Steamit brand by voting for people just because they're popular, forcing them to produce some good content. It's a maturing process. It'll be interesting to see what Steemit grows up to be.
I may have inadvertently muddied the waters. I didn't mean to say Steemit will replace Facebook in functionality. More that it is the future when it comes to content and sharing. There's so much on Facebook that I really don't need to know, or even want to know. I'm with you in that STeemit is just a seedling right now, and can easily wither, but it shows great promise. The faults you mention are there, certainly, but as this evolves, we may find that there's self-correcting going on. The beauty of a system like this one is that it has some structure, but not too much of it. Some of its evolution will be user-driven, and at that point it will depend on the quality of the users, the early adopters being a key part so long as they have some sort of common vision. It can still turn stillborn with ease, but like I said, it does show promise... Thanks for the feedback!