(CNN) -- The sisters Kardashian -- Kim, Kourtney, and Khloe -- don't have to spend millions on focus groups and dynamic PR strategists to get noticed: Twitter does it for them. In an interview to air on Thursday's "Piers Morgan Tonight," Morgan pointed out that all three are in the top 100 list of people being followed on Twitter worldwide: Kourtney is number 72, Khloe is number 47, and Kim is the sixth-most followed. With 6 million followers, she's neck and neck with President Barack Obama. Kourtney called Twitter "the best decision-maker," pointing out that she Tweets everything from potential perfume bottle designs for the sisters' signature fragrance, to outfit dilemmas, to asking fans what she should have for dinner.
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The Kardashian sisters credit Twitter with helping them make major decisions
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The sisters tell Piers Morgan their marketing and fashion savvy help keep their brand going strong
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Kim Kardashian says her most extravagant purchase was a $115,000 wristwatch
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See the full interview with Kim and Kourtney Kardashian on "Piers Morgan Tonight," 9 p.m. ET
"If you know your body type," said @placeholder, "then you can dress to feel -- its like, 'Fake it until you make it' is what we always say."