• I want to share some ideas of using voicethread
  It´s simple and easy
• focus on the content instead of the tool; can serve as a form of free writing
• encourages collaborative storytelling
• ability to use powerful images - one or many
• users can zoom in to see detail and out to see big picture (haven’t figure that one out yet)
• ability to add text
• easy to capture voices
• inspires ongoing conversation about each image
• build fluency, precision and voice in second language
• new dimension for creative analysis of historical photographs, maps and artifacts
• ability to give and receive feedback from peers, teachers [formative and summative assessment], parents and other relatives, local and global community
• can be used “as a storytelling tool, a deep thinking tool, a research tool, an expository communication tool, and even an asessment tool”
• allows for differentiation to accomodate different learning needs and styles, another option for struggling or reluctant writers

 VoiceThread can be a tool in creation:

• capitalizes on creative talents
• motivates digital generation
• can suit many purposes: informative, quesitoning, historical, autobiographical, etc.

“A single photograph, capturing a single moment, can represent multiple stories.  This site collects and invites participation in the telling.” 

• create an photo album of your school or library narrated by students
• share oral reports about research through digital story
• opportunity for students to develop interview skills
  • interview techniques
  • build confidence with peers
  • asking open ended questions

• help students conduct research
• synthesize large amounts of content
• gain expertise in using digital communications and authoring tools

3. Stories that Inform or Instruct  

• introduce new material
• use as an anticipatory set or hook for a lesson
• enhance current lessons
• make difficult content more accessible

As you can notice,voicethread is an important tool we can use for learning purposes.If you read all the informantion you will see that there´s no reason for not using it.
In addition I want to mention that I like it better than voxopopsince voicethread has more optins ,so its prefference is obvious.
Regarding this technological tool,I like it because  we can be creative.We can comment,add closed caption,text,etc.and work with students effectively and creativily.
HERE ARE SOME STRENGTHS OF VOXOPOP.I THINK THAT THEY ARE NOT SO MANY..
  Strengths

• allows for real communicative speaking and listening
• its free
• you have a good record of examples of your students speaking that you can listen to any pronunciation problems
• assess their progress as their speaking develops
• helps with ESOL students
• students can subscribe to the feed and update on their iPod, phones, computers when a new message is added 
• After reading this material you can draw your own conclussions.
• Hope you like it.