Every competitor must make their own decision as to how far they want to go in terms of photos and/or videos. But there is a major difference between hardcore porn, softcore porn, and just artistic pictures, with implied nudity or semi-nude.
You should know that any picture you take will eventually end of somewhere, in this age of the internet, so if you are comfortable with nude pictures, then fine.
Marzia and others were confortable with posing for Playboy, but even that is not hard core pics like Hustler, or worse.
Implied nudity, if done tastefully, looks great, but you need to feel comfortable with the photographer, and trust them that they won't put your picture anywhere.
Nude photos is a different story. Topless photos, here in Los Angeles, have been done by a myriad of actresses with no disrespect at all. Implied nudity not a problem either.
Full nude is a different story. Artistic nudity is your choice, but what I call porn are full on action shots, etc. There is a difference.