Broker_Imba is a small addon designed to show you at the corner of your eye quickly how many buffs/debuffs your current raid group provides out of the total available (which is 23 different kinds as of 4.0.1).
The tooltip for the LDB display provides further information about which ones you are missing.
In order to KISS, the addon does not list who provides what debuff, who COULD POTENTIALLY provide what debuff (you should know this if you are a raid leader, dude), or whatever else you can think of. It just shows which buffs/debuffs you don't have, and a total count like 20/23.
The project screenshot shows Imba displayed through the Blockoland LDB display addon, but please note that there are dozens of different display addons for LDB brokers out there, including ones like Bazooka, Fortress, NinjaPanel, and so forth.
Remember to file a ticket if you find a problem or want to request a feature. If you want to help translate Broker_Imba to languages other than English, you can do so at the project page on wowace.com. Thank you!