Whoa, this took us COMPLETELY by surprise!
Here we were almost convinced Miley Cyrus was going to be the next MAC girl when Rihanna comes out of nowhere and totally steals Mileybird's thunder!!!
The birthday girl tweeted a pic (above) of her collaboration with MAC featuring a set of makeup goodies, including eye shadow, lipstick, and lip gloss, with the caption:
Tags: chris brown, estee lauder inc, john demsey, mac, mac cosmetics, miley cyrus, rihanna, river island