Research-focused schools will primarily be interested in your program of research. Do you know what you plan to do next? Are your plans realistic given the resources/location of their institution? Will your plans lead to grants and publications? Is your intended research program sufficiently different from that of your mentor's research program? Make sure you have thought through these kinds of questions and are answering them all the time during the interview day...that is, you should talk about your research plans when asked about them directly, but also be sure to convey the message that you have clear, fund-able, publishable research plans whenever you have the opportunity. You also should be prepared for questions like, "what could you teach for us?" and "what resources do you need for your research?" Have answers to those questions. Have an answer to the question, "what is the first grant you plan to apply for?" and "what is the first publication you plan to produce when you start your tt job?" (and offer that information even if you aren't asked for it explicitly). I did 7 or 8 phone interviews and 5 campus interviews while I was on the market and I don't think anyone ever asked me about service, but you should have something to say in case someone does. For all of these questions, do your research and make sure your answer is a good fit for the institution (don't talk about desire to teach small, intimate seminars if you're interviewing at a school where most classes are large lectures; don't talk about your plan to integrate fmri into your research at an institution that doesn't have fmri equipment; etc.).
A couple of times, people asked me really specific questions about my previous publications (e.g., "why did you make X choice in your HLM models instead of Y choice?"). Review your pubs so that you are ready to answer questions like that, and also practice what you will say if you don't have an answer (which happened to me a couple of times).
As others have said, don't forget to pay attention to the culture of the school and to really think about whether you would expect to be happy there. You probably really want a tt job, but trust me that you don't want one at an institution that is a poor fit for you.
Also, faculty interviews are exhausting. Make time for exercise and eating right this fall so you're in good shape going in....you will likely need to be on your game starting at breakfast and continuing through dinner for one or two days for each interview. It's a lot.