I know I'm a johnny-come-lately to this thread but I was kinda shocked to see the results of the poll.
To me, the pastor (or board - however your church is run) should be the hiring authority. If he/ she don't know anything about music, he should get a consultant or someone musically qualified to advise him/her on the matter.
Like someone said, everyone in the choir isn't musically qualified to have an input on choosing a MOM. For that matter, why don't the congregation have some input on hiring since they'll be hearers and will be singing along?
Also, music is only one aspect (although most important) of hiring. You still have contractual terms to agree on: pay, vacation, sick days, medical coverage, retirement, etc...; the choir wouldn't (or shouldn't) know enough about these terms to make a decision.