So, you need to show a pic with a personal touch, like some specific writing or so on the set. That way the doubters will be satisfied. The pictures seem very professional.
The pics might look pro if they were taken with a decent camera with a decent lens combined with a good lighting. I notice that there are a lot of amateur ppl with such cameras like Sony A200/A300 or Canon EOS 300D/400D/30D/40D, those cameras are quite decent...
My fiancee is studying architecture and her hobby is photography so she has got a really good camera - Canon EOS 5D Mark II. It's pretty awesome to take amateur nude pics with a camera like that because the pics come out really nice, sometimes they look too pro though )...
But I have to admit that there is something about your pics that doesn't really convince me about their genuinity...
From my own experience I know that almost 80% (if not more) posted stuff are either fake or stolen, that's sad but very true...