Thank you Lisa for organizing and setting this up. And  thanks for everyone's time to learn about Diigo.

Few recommendations for  a step-by-step exploration of diigo (not all at once, but at your own leisure  pace):

1) First. check out the intro video on the homepage. http://www.youtube.com/watch?v=0RvAkTuL02A

Start using  Diigo with the very basic functionalities first -- bookmark and highlight. You  may even consider using diigolet first before trying the toolbar.  

Advantage of the diigolet is that it can be just simple drag and drop,  no installation needed, and it's compatible with all browsers. Once you're  familiar with these basic functions, then you can try the Diigo toolbar which is  a lot more powerful and fully customizable.

More tips on how to bookmark  in diigo http://help.diigo.com/How-To_Guide/Bookmarking

2)  Editing, managing and searching bookmarks & tags are extremely easy in  Diigo. Please give that a try - here are some tips http://help.diigo.com/How-To_Guide/Managing_Bookmarks

3)  Once you master the basics, and would like to explore diigo more, check out this  very simple Site Tour for an overview: http://help.diigo.com/Getting_Started/Take_A_Site_Tour

4)  List & Webslides (optional) are very powerful function to organize, share  and present a specific collection of bookmarks. Try that next.

5) Groups  (optional) - good way to collaborate with others. If you are a group creator,  make sure you explore the "Group Tag Dictionary"

6) Widgets (optional) -  if you have a blog, try "blogthis" - great time saver! If you want to explore  further, check out other tools in http://www.diigo.com/tools

7) Send / Share - Diigo  offers various ways to share info. It's not necessary to invite friends into  diigo to start sharing. You can start by forwarding your discovery to others via  email first. So use Send >> Email or you can also share info to a group of  friends in Diigo directly.

8) Friends (optional) - check out http://help.diigo.com/How-To_Guide/Friends

Diigo is full  of subtle yet very powerful functions throughout. I can also share many other  advanced tips later. But those are good step-by-step to gradually get your feet  wet with diigo first.

Hope this helps somewhat.