Went in for 5 paired up interviews, plus a portfolio review. Everyone was extremely nice, talked up the company and their culture. One interview was with engineering team members, one was senior people in the more technical/statistical area, the rest were interviews with members of the UX team.
The recruiter flat out told me that they are very picky, and that they reject more resumes and interviewees than any other group at Tableau. I suspect you must nail all the interviews, the portfolio review, and get a thumbs up from all 10 interviewers to get an offer. If just one person has doubts about you I suspect that is enough for them to reject you.
Except for the interview with the engineering team members, all of the interviews involved developing a design on a whiteboard for a scenario they give you. Since I did not get an offer, I cannot offer any advice on what they are looking for and what strategy works best. I worked through different ideas, presented by reasoning for each approach. It is possible they were looking for something more structured, or perhaps something more cutting edge. They tell you there is no "right or wrong", but I could tell many of them had specific preferences for different solutions.
I saw none of what some of the other reviews had said, that they were disorganized or rude. But, I think these are all people who are passionate about their product and company and, if they do not feel you have the same passion or personality, they won't offer you a job. I suspect that in my case, one of the more senior members of the team didn't like some of my feedback about the Tableau product and my performance on the exercise, but since they don't offer any specific feedback it is hard to know for sure.