Just because a picture does not show nudity, does not make it safe for work.
It all comes down to respect, or in this case the lack of respect. Whether I surf at work or home is not the question. It doesn't matter if I surf from a church, a business office, at an automotive shop, or at home. The picture in question is suggestive of sexual activities, which makes it possibly offensive to others. You need to respect the fact that people can get offended by such things. And if a female co-worker was walking past my office while I had that picture up on my monitor, it could offend her, getting me in trouble.
The thread title is completly devoide of information about what the thread contains. No, it does not say "Click here". However as a curtiousy to other forum members all thread titles should reflect the nature of the thread. As humans we are curious and when a thread appears with "WTF?" we are curious as to what made you say that. But if this thread said "WTF? bored girl's dorm room pictures. Possible NSFW" or something of that nature, it would be obvious that 1)- the thread had pictures which would slow down the surfing of dial-up members, and 2)- let people know there may be pictures attached which are possibly not safe for work.
It all comes down to respect of others.
My intention is not to start a flame war, and I've said what I needed to say. Feel free to reply back with your jouvinile comments if you want.