couple of things to keep in mind:
1. if someone you know comes across the pic here...well then they were visiting the site, right? they would, in essence, be "outing" themselves to expose you.
2. depending on the makeup, no one would immediately identify it as being you (I am an example since I sure look very different in my guy mode)
3. you could post it for a while, then remove it. the images link from here, so if removed from where it is hosted, it won't appear here anymore. (avatar pics are the exception to this tho)