I have an excellent example: The Citadel Party.
Look at some of the comments the female crewmembers make.
Tali will make a comment very strongly hinting that she fantasizes about a threesome with a female Shepard and Garrus if Shepard and Garrus are together.
Jack will comment that she would have sex with Tali if she was drunker.
Miranda and Jack can be asked to told to kiss one another already by Shepard.
Three characters generally considered to be straight. Who won't begin a romantic relationship with a female Shepard. And all of them of given pretty heavy lesbian subtext. And that's just the ones I know about. There's a lot of character combinations for the party.
Look at Brooks and the Clone. The way Brooks touches her is rather suggestive, somewhat hinting there's more than just business going on between them.
Now here's the interesting part: Nobody complained about it. In fact, so far as I can tell, nobody even noticed this general phenomenon. Players, including female players, seemed pretty squeeishly thrilled at these little touches. I thought they were a nice touch myself.
Now, do you think things would be the same if it were straight male characters making such comments at one another?