News/ @RobKardashian and @Rihanna Spend the Day (and Night) Together Go-Carting, Clubbing

Rihanna and Rob Kardashian were spotted spending the day together Saturday, going go-carting at the Racer's Edge Indoor Karting in Burbank, Calif., and then partying later on at Playhouse nightclub in Hollywood.
The "Where Have You Been" singer sported an oversized lacy letterman's jacket for the fun occasion, speeding around the track with R.Kardashian and a group of friends (and winning the race against the E! reality star).
So, should we put these two on a new couple alert?
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We'll just have to wait and see.
R.Kardashian has been dating singer Rita Ora, whose style and sound has been compared to that of the Bajan beauty.
Rob and Rita recently tweeted photos of themselves with a fake "Rita" tattoo on Kardashian's hand and a fake "Rob K" tattoo on hers.
Sources tell E! News that Chris Brown was also at Playhouse Saturday night, but the "Turn Up the Music" singer reportedly didn't join Rob & Ri-Ri's party. why??