"Employers are looking for technical business analysts that can link their technical and business teams through solid knowledge on both business intelligence and technology concepts. Amongst the technical questions, emphasize your communication, problem-solving, and relationship-building skills. You may be asked to provide examples of previous data analysis and data mining, as well as how you would handle a situation where not enough information was given, but a recommendation was requested anyways. Be prepared to always reference specific situations to back up your answers."
It wasn't really difficult. If you know the cookie cutter questions, you can easily walk through this interview. I have added a question when I interview people: What is your passion when it comes to business analysis? Why do you want to be one?
Understanding a part of the business well enough to come up with effective solutions that require minimal effort and then getting the required buy-in from other people in the organization. The political dynamics are an important reason for doing the job.