Posterous had a good run, but after 6 years (is that right?) the service is shutting down April 30th. Back in February Sachin Agarwal, the Founder and CEO of Posterous, made the announcement. In his words they are shutting down Posterous " in order to focus 100% of our efforts on Twitter."
I made the migration from Posterous a little over a year ago now. Back in March 2012 I posted directions on how to migrate your posts. If you still have a blog on Posterous you have basically two weeks to figure out where to move your blog. This isn’t your taxes, don’t wait till the last day to migrate!