How is describing a person as 'sexy' or 'attractive' sexist exactly?
Now, I'm sure some men (or women) can successfully use that word to describe their colleagues and still work productively with them, but quite a few men can't. For an egregious example, see this profile about Sheryl Sandberg: http://www.newyorker.com/reporting/2011/07/11/110711fa_fact_...
"Dina Kaplan, the co-founder of Blip.tv, says that when she met with angel investors to raise funds she dressed nicely, and in a meeting with a potential funder he told her, “Here’s what we do, Dina. We’re going to spend half the meeting with you pitching me, and half the meeting with me hitting on you!” “I felt nauseous,” she says. “I tried to laugh it off. I asked, ‘Of all the things you’re working on, what most excites you?’ He said, ‘Seeing you naked tonight.’"
When you've got men like that out there describing their female coworkers as sexy, you're going to have to work pretty hard to convince women not to lump you in with them. It's unfair, but that's how stereotypes work.
As long as you describe all your male presenters by how they look -- then it's not sexist at all.
I've been to a math talk where the speaker was introduced as the "most buff mathematical physicist in the US". It was probably true - he was also an amateur bodybuilder. Most speakers don't get such an introduction, only the ones with a distinctive (and good) appearance do.
(Similarly, in a CS talk, a speaker was introduced as having "the greatest shirts in all of computing." It was probably true - I've never seen a more blinged out shirt outside of a Filipino nightclub.)
It depends on how you describe them. Straight men have odd ways of thinking they are describing appearances of men in the same way as women, when in fact they are sexualing the women and then complimenting how sharp a dresser the man is. They give straight male compliments to men, rather than sexualising them.
as I said elsewhere, If you want to see how men can be sexually idolised, look at the gay community. That's men looking at men. Look at the people at gay pride parades, soft core porn or adverts aimed at the gay community (e.g. for gay bars). (Or go to amazon, look at the DVD covers for gay films)
Do you see sharply dressed men with a fine hair cut? No, you see abs, you see topless men, you see bulges in tight briefs, you see wet speedos. This is how you could sexually exploit men's appearance.
If you just act like the cast of Mad Men ("Nice tits Peggy, nice shoes pete"), you have double standards.