Rated 3 out of 5 stars
Diigo is a great service, I don't use much of it's capabilities, but I find it reliable. This toolbar is impractical to work with. I have it hidden and only show it when I need to use something from it, but that's not exacly quick use.
The other think I don't like (hate it, to be mor exact) is editing the Sticky notes.(Sticky notes are why I have installed it.) Say you write some longer note about a section of a web page you try to understand. Now you switch browses tab a to look for aditional info. You get back to then note you were writing...and voilá it's gone!
I you only could find it in Lazarus, but even that is not possible...
To sum it up, does it's job, but contains some flaws and inefficiencies.