That day is here. The site will shut down sometime today, after which time blogs will no longer be accessible. If you haven’t moved your blog off Posterous yet, you’ll have an additional 30 days to access your data after the shutdown. After that, all blogs will be permanently erased.
I never used Posterous. I’ve been aligned with WordPress from the beginning. I do, however, support Post Haven, in all aspects except its name, but that’s another story. Post Haven, being built by previous founders of Posterous, Garry Tan and Brett Gibson, definitely know what they’re doing. WordPress suffers from having to support the oldest legacy code in the world and maintaining support for garbage shared hosting. Post Haven, after the four year beta period of Posterous between launch and acquisition, should be well built and among other things, great for people just wanting to write long form on their own paid for plan.
And if Post Haven for some reason doesn’t work out (and there’s no reason it shouldn’t, you’re doing it wrong, most likely, in that case), there’s always WordPress and soon, Ghost.