if your company is anything like mine (i'm suspecting some reasonable similarities given the same industry) part of the interview is to see how good of a fit you'd be with the team, not just your technical chops.That's pretty similar to the interviews for my current job, but never before was there 7 people at once like that, all of whom I'd never met (despite being within my company, albeit a massive one).
I went from thinking I had 0 chance at the beginning to optimistic by the end, so I'm happy overall. I would think they expect a slow start with that approach, anyway.