That's exactly the idea. It's a bootstrap. You use the systems that are in place now to boot up the successor.

It's never either/or. You use everything that works, that has people on it that you need to reach, as long as they welcome you.

This has been the problem with Google-Plus. They don't have an API that lets you post to it. But Twitter does. To everyone who follows me on Twitter, they don't have any idea that I'm not really on their network. In every sense that matters I am.

But when Twitter goes down, I keep posting, and people who are hooked in my feed still get the new stuff.

Isn't this exactly the problem? Keeping a service alive in perpetuity is missing the point because it's the communication that's important, not the service upon which the communication flows... Human communication is inherently temporally limited. If you ignore that, you're not gonna be heard now, which makes you even less likely to be heard in the future.

EDIT: I guess I'm just saying: nobody reads old messages on this sort of service. If you're not targeting "now", you're starting off with an immense disability.

[1] - a microblogging site that uses ostatus; we integrate with identi.ca. code here: https://github.com/hotsh/rstat.us