I almost feel like it's their job to seem as vague as possible concerning whether or not they're interested so I wouldn't read too much into it! As stated, the fact that they are interviewing you has to be positive so I'd try to just wait the few days as calmly as possible. As I type this, I realize how difficult that will be, but it's worth a try. At this point, your chances of admission are very high. You're on the short list! Good luck!