This is my main concern. I'm totally fine with romances or no - if the writers feel willing and they have the time, and fans want it, why not let 'em have it? It's optional (or, at least, it should be) and harmless, and I find it rather suspicious that people would get so uptight about sexuality or romance when it isn't mandatory (assuming, of course, it doesn't hurt the quality of the writing or game otherwise). Reminds me a bit of those people who disapprove vehemently of certain language, and then go looking for all the naughty words in the dictionary to make sure they aren't there.
However, a big thing for me is interesting, in-depth characters, who I can interact with in various ways and learn more about. Although I'm sure other games have done it, or leaned toward it, I always remember how awful it was in ME2 that I couldn't watch a character develop or have any or many conversations with them (more so in comparison to a P.C. that was romancing them) because I wasn't the right gender or didn't try to woo the character. Garrus, Jacob, Miranda, and Tali were among those that seemed especially, blatantly stuck as romantic interests alone.
I believe Dragon Age: Origins was a lot better about it, though I'm not positive. I recall being able to properly speak to the characters, each having their own problems and ideas/beliefs, whether or not I pursued them romantically. It wasn't a requirement to get character interaction and development, and there wasn't weird favoritism over which character was given more attention by the game. Fallout: New Vegas was also very good about it, when it was at its best (Veronica, Boone, etc.). Though some companions were neglected, and I don't recall any potential romances existing.