I used it this summer for a training I did and it is an effective visual tool ;) Combine it with Livebinders & Symbaloo and you have a powerful set of tools to share resources in three easy to use formats.
A visual bookmarking site where you can make public bookmark pages with comments to share with students and colleagues by sharing the link. Great for setting homework.
http://ictmagic.wikispaces.com/ICT+&+Web+Tools