It's not a negative, but by the same token it's not a positive either. One thing I always taught job seekers is "ask for the job". In the future, if the interviewer doesn't ask when you can start, ask the interviewer, and get in a statement about how you really want to work there.
Given he asked for your references, I'd say that you're not out of the running. Hiring is a huge pain for employers and they won't waste a picosecond bothering with someone they are not seriously considering.
To sum up: If they asked for your references, they are interested. Don't worry about it, but keep applying, the job isn't yours until you're sitting at your desk.