This article at JobSnake passes along tips on what things you should research about before doing an interview:

When you go in for a job interview, you’re not just a candidate seeking a job. You’re a potential problem solver and contributor. To play that role effectively, you must be armed with the right kind of information. That’s what pre-interview research is all about.

Break down your research efforts into four broad areas. That’ll make it easier to manage and also ensure you don’t leave anything out.