The only difference I can think of is the Black Widow/Lady Killer perk.
Which I think Black Widow is better, because the game has more men typically, you can get more damage on them.
Also you can convince Mister Burke for more money for blowing up Megaton... thats nice >:D
Plus sexysleepwear is actually sexy.
^ Basically what he said plus Naughty Nightwear is Naughty looking. However, the Lady Killer perk on the AntAgonizer is a must-see in my opinion.
In Fallout 3, if you save Megaton (The Power of The Atom) and are female, Jerico will send you love letters. I don't remember the specifics. You may need the Black Widow perk. Check Jerico's page for additional information.
As mentioned above, there are more Male NPCs in the game, so Black Widow/Ladykiller have more of an advantage. The only actual difference in NV is that females cannot fight in the Legion's Arena.