I have spent the last few days, off and on, learning more about the diigo tagging system. I have also been both comparing it and and trying to combine it with the del.icio.us and StumbleUpon tagging systems.
The best thing about diigo, so far, is that you can highlight passages of interest and attach stickynotes for comments directly to articles or websites that have caught your interest. You can also take those comments and send them to your blog as a draft post. The draft post will include an annotated link that will take the reader directly to the particular webpage with sections highlighted and comments attached. Other diigo members can do the same, creating a conversation on the webpage itself. Trouble though is that the annotations don't always seem to show up in the same way, though that may be me or my computer rather than diigo.
Similar to StumbleUpon, there also seems to be a greater opportunity to link up with others than there does with del.icio.us. So far two other (diigoites ?) have asked me to link with them. One is an organization, Eco20/20, a worthwhile organization, which is asking everybody with the right tags to link up. They also asked me to join their group, which I have. Right now it seems that they have more friends (56) then members (15).
Another group that I ran across in my webtrekking through diigo country was edtechtalk an organization with a diigo group. They have 214 members. As their website says, EdTechTalk is a community of educators interested in discussing and learning about the uses of educational technology. This is another example of a professional organization using diigo for collaboration. What I found interesting was their discussion on whether to use both diigo and del.icio.us or to dump del.icio.us.
As far as which one is better, for inter-active connections among a particular group diigo would seem to be far ahead. I also like their webslide feature, though it seems that I need to re-install it on some of my posts.
For testing which was better in the dissemination of websites, I searched for the word "entropy". I got 133 hits from diigo. It gave me 3 of my sites even though I had not tagged them "entropy". What was particularly interesting was that diigo gave me "linguistics" as a related group with 4 members. StumbleUpon only gives you 10 featured sites but gives you 30 other fellow stumblers who are also interested in "entropy" sites. You can then decide to stumble other sites, which can be cool since I am OK with utilizing random inquisitiveness or being open to serendipity. Mag.nolia gave me about 100. The winner hands down was del.icio.us with 2,680 sites. There are repeats though with all the systems because different people tag sites differently.
So I like diigo's interactivity better than either del.icio.us or StumbleUpon. I will still use del.icio.us because most people who find websites featured on this weblog find them on del.icio.us. Which works out because I can automatically save to diigo, del.icio.us and mag.nolia. I do like the formating and serendipitous approach of StumbleUpon better than diigo or del.icio.us, but that is also ok because I can save from del.icio.us to StumbleUpon using a greasedmonkey script.
My latest experiment using diigo was to use the diigo blog feature about a Penelope Trunk post, highlighting certain sections and publishing it to this blog. The diigo annotated links took me to the posted with my comments highlighted. Finally, I saved this under StumbleUpon using their toolbar.
Now the question is whether it is worth it. It it is not that much more trouble, a few more clicks. Each tagging system has its own strengths. The answer depends upon why you are saving the website in the first place. For a weblog seeking new pathways through learning while endeavoring to share any worthwhile finds, the combination could be the best approach.