Congratulations, Stacey!
I'll second most of what Howard said. There will most likely be a panel of interviewers and their questions are likely to be extremely well thought out. They will have already prepared a scoring matrix and compared how the info on your CV tallies with the essential and desired characteristics of the ideal candidate. Make SURE you go over the desired/essential list and know how you qualify for each of them. And britwife is right...there will most likely be a question about cultural sensitivity...I was asked what I thought would be the most important social factors affecting the people I would be working with--I said socioeconomic and religious/cultural and expanded on that.
You should find out fairly soon. I found out the same day...when DH was job-searching he usually found out within a week or so.
Wear something professional, but make sure that you're comfortable. I'd suggest some well-cut trousers and a jacket or a skirt suit. Skip the perfume, loads of accessories, and things that are ultra-trendy. Think classic!
Also, make a real effort to speak slowly and clearly. I tend to talk too fast for most people to understand me, so I was very aware of that (and my accent!) during the interview.
I'm keeping my fingers crossed for you!