The numbers indicate requests (as in HTTP requests) attempted by the tracking companies. Green (or checked) indicates the requests were blocked. Gray (or unchecked) indicates they were allowed.
We'll beef up the help doc (https://disconnect.me/d2/help) to clarify.
Some pages I visit show 100+ requests but when I enter the add-on it only shows 2 advertising attempts and maybe 1 analytics request. Where do these other hundred requests come from and were they effectively blocked from communicating with its third-party provider?
Disconnect 2 basically replaces HTTPS Everywhere, which I find nice.
The number of requests in the dropdown menu should add up to the number of requests in the toolbar counter (we do group requests by company, which Ghostery doesn't do, so you will see less rows in Disconnect's UI if that's what you mean). Do you have a site where the two aren't equal?
One criticism: It's not clear from the popup what the numbers mean. Are they counting scripts loaded, or scripts blocked? The same for the colouring. Are coloured icons blocked, and greyed ones allowed through, or vice-versa? And of course the tickboxes.