Speedtile is a super-easy social bookmarking site that shows thumbnail shots of the websites you want to bookmark, allows you to have a public page to share them, and to tag them into categories.
This last capability is particularly important for the way I use these these kinds of applications with ELL’s to promote higher-order categorization skills with images. Unfortunately, though, it doesn’t appear that you can write specific descriptions under each url added to your personal page — only a tag for all the sites you are adding to that broader “tag.”
Nevertheless, I’m adding the site to The Best Social Bookmarking Applications For English Language Learners & Other Students.
Thanks to Go To Web 2.0 for the tip.