Don't panic too much about preparing; just make you've read what you say you've read...my interviewers didn't really care how much I knew, they just wanted to know how I thought. And groovymouse's advice is really good if you have interviews that might overrun (mine did); at least then you won't waste time trying to figure out where you're going after your first one and it's so much less stressful if you know where you're going.
I'm gapping at the moment, so I'll see any lucky applicants next year hopefully!
I do sometimes wonder if the interviewers spy on TSR...it would be such a wealth of info!