Yes and no. Yes, in the sense that I feel most trans people (self-identified, identified by others - doesn't seem to matter) have some sort of common experience of having had to slug it out with the society at large as far as their sexes and/or genders are considered. It does create some community. But in my opinion it's based on oppression and very little else.
No, in the sense that the life experiences of various trans people differ to such a great degree that it's really hard to find common points of self-interest: what would a third option on legal sex do to me? Either nothing (if you can choose for yourself - I'd obviously skip it as I ain't no third sex), or a great deal of hassle and harm (if it's chosen for you, whether you like it or not).
I think it boils down to how trans people would like to be treated by others. Some of us (see, community) would like to be treated in a separate way with regards to law, medicine, or social interaction. Some of us would rather not have anything special (Oi! That'd be me!) apart from correcting errors in documents. Those wanting new, different options tend to fall to the transgender/genderqueer side, and those of us who don't, tend to fall on the transsexuality side of things.
Now I don't propose to have a solution to this problem; it has to be sorted out politically: by discussing, arguing, fighting amongst ourselves. But I am saying that there needs to be options: we've got to sort out a way in which transgender/genderqueer people can live safely and respectfully, and it's got to be done in a way that respects trans women and men who'd really rather just drop the trans bit altogether. In other words, no non-consensual third-gendering, no branding people as trans, no forcing people into sexes or genders at all. The third item on that list being much harder to implement than the others, but it needs to stay on the list for us trans women, too - it'd have some serious potential of saving our girlhoods from being a nightmare they all too often are.
All of that has to, in my opinion, be sorted out by the people affected by it, that is, trans people of all kinds, even the people with trans pasts. And in that sense there must be a community if we're to do the right thing.
But will there ever be a trans community in the sense people see there is a gay community? No. And I don't think there's much of a gay community, either. Gays come in all colours and sizes and varieties. What I would see superficially as a gay community is fairly likely just a very visible subset of all the variety of gay people, and 'cos I'm not a part of it myself, I just tend to do the very human thing, and lump 'em all in the same heap of gay. But it's not the truth about them, it's my simplification, and I'd really better not make any political statements based on my silly generalisations.
I'd like to pontificate on the reasons for trans people falling so afar from each other: I think a large part of it is due to fear, uncertainty and other contradictory feelings. The following is highly speculative, so try to bear with me.
From my pov, transgender/genderqueer people seem a tad unrealistic at times. It's all very good to demand equal rights for all people (and especially themselves), but actually implementing those rights can be a bit of a bastard. And not only that, but it'd be neat if the said implementation wasn't an ad hoc -mess, but something that can be applied in a general sense, too. For example, consider scrapping legal sex/gender. (I'd sure like it, no harm would be done to me even if I am a woman - I'd be just as much a woman after that, too) Marriage legislation would have to be rewritten. Parenthood legislation ditto. Military conscription has to be redone. All kinds of registers have to be redone. Passports, DLs, the lot - it's not a trivial task, nor is it in any sense clear that that is actually possible to pull off in one fell swoop; it requires a lot of political will. Just yelling "our rights now" (or even worse: "my rights now") won't do it. Actually talking with politicians, or becoming one oneself are steps into that direction, but what little I see about transgender/genderqueer politics, it's all about anarchism and not getting dirty with the state and let's have a revolution. Yeah, right. Pull another one. You guys couldn't have a revolution and even of you could, you'd just end up oppressing in new ways. It's happened so many times already - what makes you think you're different? And please, pretty please, have a look at the sexism in your midst. There's a reason why there's so few trans feminine spectrum people present in those circles.
From transgender/genderqueer/queer pov, binary trans women such as myself probably raise some squicks. Our surgeries do that. Our trust in medicine, our delight in our conditions, nay, make that illness's, medicality seems to do that big time. I love what I got from the surgeries I've underwent. I think medical science and skill is just great in some respects. Micronised estradiol pills <3 <3 <3 For people who don't trust medicine the way I do, this must be a bit distressing. My dependence on modern Western medicine must be a bit depressing to someone who likes to do things by hirself, for hirself, and if a thing can't be done in an ethical way, it'd perhaps really better not be done at all. I also suspect my apparent femininity must raise some eyebrows, too - the combination of the determination needed to get medical and legal reassignment and then just flowing into this new almost ridiculously standard sex/gender must be a bit mind-bending - I'm not sure, but I feel the thinking might go along the "she went to all that trouble and fighting to get that bog-standard woman stuff, instead of this gender/sex neatness we have?"
I don't have the solutions. But I think a description of the problem is the beginning of the search for a solution. This is my offer.