[mmaibff]

She may have chosen to title it M because it could mean a lot of different things and a lot of times with songs what the Artist writes and what we interpret are completely different things. From the PV you could say that M stood for Virgin Mary because it seemed that Ayu was praying to a saint. But by reading the lyrics you can interpret it as Mary of Magdalene because it states "Maria" There is someone I should love;
every person who has ever been hurt..." Mary of Magdalene is sometimes referred to as a prostitute and yet she was forgiven for her sin, so she should be loved like everyone else. Other say that it may be Mary of Magdalene because M is her initials and that may be why its just M and not Maria. Its been a while but I've also read somewhere that Ayu have written this after one of her friend told her about (someone they knew I think) named Maria so really all this debate about whether it was about either of the first two could have wrong.

The M could stand for Virgin Mary, or Mary of Magdalene, or someone else completely. But I don't think she chose M because she afraid of getting a bad reputation. There are a lot of artists that have song title that has to do with religion, I mean Gackt has a song called Maria and that never cause any problems and his song Jesus came out last month, acid android has a song called Jesus Christ, and in HYDE Faith Album there where a lot of hints toward Christianity(because it was based off of it).

On another note (no offense to anyone who really religious but) in Japan they see Christianity/Western Religion kind of like a fad/trend sort of thing I doubt it would affect the artist reputation there (in my opinion I don't think people are all that religious or well strictly religious in Japan that it would offend them), it may affect there reputation to some fans in other countries. But I don't think artists are going to change a song title so it doesn't offend anyone.