It's not that I have any problem with nudists or nudity. Instead, I'd like to say that those parts can be celebrated by being a bit selective of when they are shared with others, and make their appearance not so common beyond showering, sleeping and sex.
Nudity is special in my book and should be reserved for special occasions, so I guess like Confidential, posted above, I would prefer hangout time in shared house spaces to be in boxers/briefs/PJs etc. After a shower, absolutely shave naked at the sink, or get naked to sleep at night- its all good- and i'd expect any and all sort of reciprocal behavior for me without judgement or expectation.
If we shared a bedroom space ..., well, more is gonna be seen regularly. Soft, semi, floppy or hard and throbbing, it's fine, because a roommate situation should be a successful friendship that comes from trust, respect, and compromise- and comfort where nudity lies will balance out if everyone is honest and strives for a safe space for all. If not, move on.
If I am staying at a friend's home, I certainly want to be invited back, and so it's important to be respectful to the host and remain a bit more reserved and conservative than i would be if I was alone. I will at least stay even to the dress of the host and/or other house guests- being aware of how everyone else is acting around me, and proceed from there. If it was a true CLOTHING OPTIONAL space and everyone was completely textile free, then I'd probably participate.
If I was staying at a hostel with strangers, that's when I could (within legal constraints) choose to set the tone for others and hang out wearing less- especially if i knew i would never be there or with those people again. But be warned: if there is an expected space where people would have reason to be naked- such as a locker room, dressing area, or swimming pool, I won't be towel-dance shy.
If my housemate wanted to watch something spicy, and decided to strip down for some sexy playtime, well that's a good reason to get naked- meaning I would give him some private time to indulge, or wait for invitation to join in myself if I was in the mood.
If nudity comes from one of these 3 reasons, it is no longer 'weird' and I think it's easier for others to be comfortable with it.