Odo only liked women. Linking isn't sex, it's something completely different. Odo did do it human-style with the Founder leader (side note: Think about that and try to sleep tonight ), but the only person he was ever actually in love with was Kira. So no, not bi or gay.
Well I guess if you put it that way... But here's how I understand it. (And I'm probably wrong but I've never actually discussed changelings before so I don't have any other viewpoints.) Well I can't remember what episode it was and I don't feel like looking it up but the female changeling was explaining to Odo all about changelings and Odo asked how many changelings there are. She answered with something along the lines of, "One drop can become the whole ocean and the whole ocean can become one drop." (That's not exactly what she said but close enough.) Odo was surprised when he realized there was only one but many. So what I'm thinking is that if every single changeling is a part of every other changeling than genders probably don't matter. I mean think of it like this. If every human on earth linked like the changelings in The Great Link, we would all experience love for every single other human. So it wouldn't really matter weather or not we loved a male or a female because everyone would have loved both and everyone would be a part of the person being loved. I don't know though. That's just what I think.
Also on the subject of OD in that episode I still think the chick wanting in his pants in the beginning is a changeling she is just way to umm wanting him you know?
I wonder if he even bothers to form genitals under his "clothes" on a daily basis. -or just on special occasions.
Odo is aesexual, but there's evidence that when he makes love in humanoid form he feels the same pleasures. Shapeshifters are genderless, so why would you even think that Odo linking with Laas was homosexual just because they both pick a male form for interacting with humanoids?
Changelings may be without gender in their natural state, but if a particular one of them - such as Odo - routinely selects a male humanoid form, I think it's likely that they have chosen a gender. Odo always looks male, so therefore he considers himself male. And since he only likes Kira...well you do the math.
I don't think he really cares about the gender of a person. Kira just happens to be female and possess the qualities he finds attractive.
True. Now, when I first heard of his character, I was expecting a less gruff character--rather like the traveller...making him a character more like Pie'oh'pah from Imajica. I was actually hoping DS9 would be surreal But Odo was more gruff than that of course. David Banks in his books had two different sexless races--Cybermen all seem masculine. The denizens of the ice world more uniformly feminine. Odo is Chaz--he is a cop, and as such seems more male.