I think, assuming they've intended Serena to be a lesbian all along, they could've dropped a few more hints. I mean, in the episode before this one, they've got her talking about that contractor guy and saying something about how you have to be a woman to understand the allure of the "bad boy" to women. That doesn't necessarily indicate anything, of course, because I would say the same thing to two men who were wondering why a woman would be attracted to a man like that. I would say, "Hey, some women like that bad boy type." I know this not because I am a straight woman, but because I know women. However, without any further comment, it could easily lead one to believe a woman is speaking from her own experience.
I never suspected a thing about her sexuality. It's been obvious for some time that she is often at odds with the DA's office on issues like who should be charged with which crimes, exactly; it's obvious she is less "law and order" than McCoy, and much less so than Branch. I always took her differences of opinion to indicate a difference in politics or just that she has a different perspective on criminal justice. I agree with Branch about that issue - she's far more suited to advocacy.
But I digress...
It felt cheap and out-of-the-blue to me. If they were going for a shock there at the end, it was enough of a shock to me that Branch fired her. The whole lesbian thing just felt tacked on.
Is it good? Is it bad? I don't know, really. I could argue that it's good because it forces the viewer to realize that a character they've known for four years has been a lesbian all that time and that, whether they like her or dislike her, it had nothing to do with her sexuality. It reinforces the notion that sexuality shouldn't be a factor in one's opinion of others.
I could argue that it's bad because we lost four years of lesbian (and general queer) visibility on one of the most-watched television shows on the air today. It would have been a piece of cake for them to toss one or two
unambiguous tidbits into a few episodes. A handful of lines or less in four years. That way, we (the audience) would know she's a lesbian and we would still get to see that it's of little or no consequence - she's still the lawyer she is, the person she is, regardless of her sexuality.
I don't know what their point was in doing it the way they did, but I feel robbed.
make some room now dig what you see