For herpes to be transmitted there has to be direct contact between the virus and a damaged location on the skin or a mucous membrane. A damaged skin location can be a micro abrasion so small to see or feel.
Yes, herpes can be transmitted through saliva if the virus is active at the time, regardless of whether there are open sores or not. Either HSV1 or HSV2 can be transmitted through saliva, however HSV2 infections in the oral region are more rare and they are less likely to become active or recur, so the chances of transmitting HSV2 through saliva is lower in that sense.
If either HSV1 or HSV2 is active in the saliva, the risk of them being transmitted is pretty much the same.
In general, women are more susceptible to HSV infections than men, or more accurately, men are more likely to infect woman than the other around. Because a woman has more mucous membrane surface area exposed during oral sex, then she is more likely to be infected. But men can be infected as well. And either sex can have a micro abrasion present that would make them equally susceptible to an infection.
HSV1 now accounts for up to 50 percent of new genital herpes infections, this is likely the result of increases oral sex activities among the young adult population.