"I concur whole-heartedly, my African-American brother"
1. affirmative; For sure, ma nigga
not necessarily in any racial context.
From a branch of urban (American) slang which adds 'izz' or varients of (ie izzle/izzo) to words to create a more rhyme like 'melody' to sentences.
kid 2: "fo' shizzle my nizzle"
2. To aquiesce to or agree with a proposition or idea offered by an affable peer.