My impression of this tool is that it is similar in context to blogs in that individuals can enter content and others can comment on the content that has been embedded. The advantage of voicethread is that it is auditory which supports both the lower literacy learners and it appeals to the learning styles of the indigenous.
Having listened to the promotional videos for their ed.voicethread, it sounds like this site is well set up to supply the security necessary for an educational institute to use such tools. In ed.voicethread the Educational instructor that initiates the thread has control of the members that view it and is the only one who can allow new memebers. The system is set up so the instructor has to moderate all students comments before they are posted for members viewing/listening.
In my opinion Voicethread would support a wide range of pedagogical practices that included learners in authentic engaging expereinces. Having just completed two oral presentations and reflecting upon the way i reacted to them, I would be happy to employ this type of technology in replacement of such assessment tools. Students would be able to orate their learnings without the pressure of being stuck out in front of the class with everyone watching. The assessment would be performed in a way that supports the learners to maintain a sense of comfort and order, which Marzano and Pickering (1997) identify as a key aspect to developing positive attitudes and perceptions
Marzano, R. and Pickering, D. (1997), Dimensions of Learning; Teacher's Manual, Aurora, Colorado, McREL (Mid-continent Regional Educational Laboratory)