In case you didn't know, "They're all bi." In the BioWare forums, this phrase was taken up some time before Dragon Age 2's release. The evidence gathered from a German review indicated that romance options had been aufgestockt (increased), and similar evidence kept pointing out how all the romances were available to either sex. It also came to light that Sebastian, the DLC character, was available as a romantic option, but as both chaste and heteroromantic. Naturally, there have been grumbles that the one who isn't available to their male Hawkes is the one they would have chosen.
What I would like to do is explore this game's inclusion of these options, largely making a case for why I think it worked in this instance. I will admit to having completed only one and a half of the romances (Anders is completed, Fenris is halfway through), and will also add that there are plans to more fully examine each individual romance in the Queer Characters tag we have.
Also, fair warning, there will be some spoilers, and some of the images I'm using past the cut/this paragraph will be NSFW (I also wish to thank the artists for giving me permission to use their work--I will credit each under the respective pictures).
For some, the argument is that the romances will be thrown together and not worth as much. It's lazy, cheap, etc.
My rebuttal would be that a lot in Dragon Age 2 feels rushed and lazy, certainly. I don't feel the same about the romances I've witnessed and read about from friends as yet (I'm fortunate that I have had friends report on the same-sex pairings of all four companions).
In the case of Anders, for instance, he can be seen through a subjective lens that speaks very heavily to a male-male romance in a single-playthrough to someone who hasn't played Awakening. You hit on him (...somewhat inappropriately), he makes mention of his love for Karl, and then he makes sure that you aren't bothered by this previous relationship. If you've played Awakening, the subjectivity argument doesn't seem to hold as much, as he clearly states his appreciation for women, and he doesn't seem the type to hide his sexuality. Our meta-game knowledge that he is available to women also reinforces such.
In Awakening he also goes on to talk about what a love-fest being in the Circles of Thedas can be (at least the one in Fereldan). Due to his being a mage, there are also parallels in the way that whole storyline folds out, and it left me with an attachment I did not expect to find so readily. From what it seemed like, his romance was very much written with an eye toward a male same-sex option.
Isabela is firmly bisexual, but we knew this to start. She is unabashed in her love of sex, and BioWare toed a fine line of actually writing a sexually empowered woman. I believe they tipped on to the side of a positive portrayal, largely because she also has various banter that hints at self-confidence and respect, rather than only wanting to have sex with everything that moves (and actually, she can refuse to have sex with someone in the game when you suggest it, bringing up that she too has standards). She defies the stereotype of a same-sex woman romance automatically being bonded by the hip and married, as well. Like Zevran, she takes time and a little effort to actually romance, and not just bed. Whether or not she feels played up to appeal to a heterosexual male audience? I cannot say, though I'd like to believe not.
Fenris and Merrill are unknowns to the series before this game. From what I've seen of the former and heard of the latter, their sexual histories aren't wholly explored. From what I've witnessed of Fenris's, it's not odd that I'm hitting on him, and my being a man hasn't elicited any sex-specific response. I hear much the same from Merrill. They're just bisexual, but it seems that unless you know that in a meta-game context, the game might not necessarily show you such (feel free to correct me if I'm wrong--the Wikia may talk about the romances, but not too specifically).
Before the game released, and the all-bi rumors started, I had a sinking feeling concerning where the game was headed. From what I read of many's experiences with romancing Zevran, the option people wanted was a human warrior for men, for instance. This meant they could have a human, but a mage, or a warrior, but an elf. It seemed a losing proposition to please everyone who wanted man-on-man loving.
Of course, the release of Sebastian, who is not a romance available to a male Hawke has drawn some long sighs. Sebastian is a bit of an odd precedent himself, though. He's DLC, so he is not available with the game to start (unless you pre-ordered and received the signature edition). A romance available from DLC? It's a bit unprecedented in BioWare terms. Though, he's a bit of an odd example as he, like Shale, was written to completion in that time before the game released, but by which time they'd already finished the game--they integrated him rather seamlessly by allowing certain story hooks that they could insert him without due concern.
The entire case is a bit odd, as it speaks against a lot of what we might consider common sense. One: he's not bi as the other four options. Two: he's a romance option for people who play a Lady Hawke. Considering BioWare has had inequal options in favor of male avatars before (though not in some time), this is a bit unusual not only for BioWare, but probably for games in general.
The decision to include this makes me wonder how else they might explore romance in DLC packs, particularly as DLC characters in the Dragon Age series have been more fully fleshed than those of Mass Effect 2's. As it is, there will be people disappointed, which was the danger of not having the four options we do have all be open to either sex we can choose to play.
The second argument that will come up is why there is no option for a purely same-sex romance. Honestly, while I would love that from a large studio, I don't expect it any time in the near future. That's something I would expect from a smaller developer. Naturally, if a larger studio were to offer such, most of us would look in the direction of BioWare--as David Gaider has stated in the comment sections here, the economics don't justify it for them right now.
Therefore, the four options that are open to same-sex romances? They don't seem to me to be as rushed as I would have thought. In the case of Anders, the only romance I have completed fully, the addition of expanding on his story of Karl felt specifically put in there not only as a possible way to deter people who might 'accidentally' fall into the romance, but to open up his character a bit. If I had a complaint, it would be my own desire to use the heart option in a wholly inappropriate time.
My current romance with Fenris doesn't feel as keyed in to me due to my playing a male Hawke, but it also doesn't alienate me in any way. The fact that it just exists is a nice counterpoint to Anders's romance arc.
However, the magic of this, to me, is that I could (and likely will) play the game at least four different times, romance four different companions, and never once have to play as a purely heterosexual character (though I'll likely also take that route at some point). Which is among the reasons I really enjoy this game, despite the many flaws on which I could enumerate (and which our formal review will do).
As for any arguments that it seems highly unlikely that so many bisexual people would all be traveling around? While Thedas may not have an LGB culture as we understand it, I do know that I often find myself capable of belonging to a group of like-minded individuals. In my case, that's people who are open with their sexuality, and use many different labels. It's just as often been the case that I find it remarkable when I find someone who is purely heterosexual. It's really not that difficult to imagine, and there's probably a message in there that the world does have straight people, but some of the strongest, or perhaps most integral to the history of the world, are bisexual.