Even still, I think it would be inappropriate. Part of the issue here is the anatomical differences between men and women. While seeing a women with large breasts might not seem bothersome to you, I'd venture a guess that a photograph of a closeup of an extremely well-endowed man whose penis is bulging out of his speedo (analogous to a well-endowed woman's breasts spilling out of the top of her bra) that conspicuously outlines the glans and shaft (analogous to a woman's erect nipples) would have men feeling uncomfortable at the LEAST and more-than-likely up in arms.
To take it further, just imagine if the "male programmer" stereotype was up on the slide as a "before" image with all of the insecurities of men highlighted--namely height and penis size. The "after" image shows the man visibly more endowed and taller. Again, if a WOMAN were to do this at a conference, she'd be ridiculed on the blogs for months after at the very least.
Uh, yes? Why would anyone ever do that?