Statistically speaking, men commit a huge percentage of the violence in the world, rape included. It's not to say that women don't rape, but the occurrence is much much lower.
It's hard to get accurate numbers (because so many rapes, regardless of the victim's gender, go unreported) but I've seen things that range from 85%-99% of all rapists are men. It'd be foolish to go with either extreme, so a loosely based assumption would have the percentage hovering around 90% of rapists being men. That's not to say that it isn't important to talk about female rapists, but to me focusing anywhere more than 10% of the talk on female rapists would be unfair.
When talking about rape, I think the most important factor to look at is why people rape, and not who does the raping. Again, rape is a crime of power. To have any productive talk about rape would be in attempts at trying to understand why people feel the need to do so. Simply saying that men get raped too isn't enough in my book. People already know this.
If we're going to talk about support for victims, it needs to be a broad subject. There is very little support for any rape victim; man, woman, or child. From finding ways to provide sustainable support, the discussion/solutions can be extrapolated off into smaller and smaller examples for men and women. Again though, I'd find it a huge waste of time to focus 50/50 on victim's sex when that's disproportionate to who the victims are. People who know anything already know that men get raped too. The next step is talking about rape in general. Across the board it's seen as a social taboo.