I used to do job interviews where I worked before going back to school -- we did both one-on-one and group interviews. Personally, I think the group interviews were better from the employer's perspective because you get a panel's worth of opinions and impressions of the candidate. It probably worked out better for the candidate in a lot of cases, too, because if he only gets one interviewer who's having a bad day he's got no chance at all -- with a group he's got better odds.