What's great about this is that most of the advice shared can be applied to just about any technical interview, especially in software engineering. Knowing your projects and being able to perform on the spot quite technically is always a plus, I've noticed. No matter what, I've learned, being familiar with the fundamentals of the technical area you're trying to become employed in will land you the gig, even with very little experience. Have one or two projects to explain in a sophisticated, detailed manner, and you're likely to beat every other applicant. haha
On a slightly tangential note: i too recently interviewed for data scientist positions, and ended up with multiple offers. If you need advise for preparing for data science interviews / need help understanding concepts in machine learning, i'll be happy to help. Contact info is in my profile.