Definitions by Hi Shisters James Charles here

What's poppin, what's Gucci? 

It typically means "what's up" or "how are you doing" or "how's your day?

Friend: Hi Steph, What's poppin, what's Gucci?

Stephanie: Hey!!! Nothing much wbu?

What's poppin, what's Gucci? by Hi Shisters James Charles here July 3, 2018