Before anyone can make any decision, they should know about the school system and their Deaf Education program. My local school district always talks to parents about their success rate, how well the kids do, etc. Well, a good friend of mine was an interpreter at the school system and I asked her for her honest opinion on their Deaf Education. She told me she actually thought it was horrible. The deaf kids weren't really being mainstreamed - they were at the same school as hearing kids, but were almost entirely separated from the hearings kids in classrooms. She told me in the high school, none of the deaf kids were actually in any classes with hearing students. The bottom line was that the school district would have lost money if the deaf kids went to a deaf school.
I have spoken to several people who started in the mainstream program and then transferred to the deaf school. The only thing they missed about the local school was their friends. They felt they learned so much more at a deaf school than the local public school.
So I would defintely urge a parent of a deaf child to really look into the Deaf Education program at their local school. Don't simply accept what the schools tell them. Really investigate and find out what the truth really is.