This is an older (2010) post from Nik Peachey explaining how to link a Posterous blog with the podcasting site AudioBoo for speaking activities.
He explains how to upload students' recordings directly from the classroom using mobile apps. One click puts the audio on AudioBoo and posts it to Posterous. In the way, students can listen to each other's recordings and post comments, and the teacher can provide feedback, all via the blog.
This is something I like to do with classes yet always seems to involve a lot of clicking on my part, and perhaps less engagement from learners as they hear their presentations days after the event. So I'll be checking this combination out to see if it will work for me.