I will assume, for the sake of argument, Facebook Connect is easier to login to than OpenID. (I have never had a Facebook account.) That doesn't change the fact that you can only use it to login with a Facebook account.

I don't think we should be in a "make your [non-Dreamwidth] account more useful" business, which I think building code to let you login from one particular website, or repost to one particular website, is. I'm not hostile to Facebook. I'd like us to move away from LJ-interoperable tools into more generally web interoperable tools, for instance.

But, I'm also not convinced by, "Half the internet has Facebook accounts" arguments, because there's no way to know when a quarter of the internet will start abandoning their Facebook accounts. Remember when Myspace was The Social Network? Now, it's what bands use instead of building a real website.