While the traditional face-to-face interview is still the most common, many agencies and companies are conducting first interviews (or sometimes, the only interview) remotely, using the telephone, Skype, video-teleconferencing (VTC) or another medium. Preparation, including researching the organization, drafting your CCAR examples, composing questions to ask the employer, etc., are applicable to both in-person and remote interviews, however, remote interviews present some special challenges.
Telephone interviews are particularly challenging since you cannot see the people with whom you are interviewing. If contacted for a phone interview, I encourage you to ask if the interview can be conducted using Skype, FaceTime, VTC, or something similar where you can see the interviewers. While still not as personal as face-to-face interviews, being on camera can help everyone stay more focused on the interview itself.