I am already happily partnered, but if I wasn't I would have no problem with dating either a FtM or a MtF transsexual. As others have said, it's not a person's bits I'm attracted to, it's the person.
Actually, the biggest potential problem I can see with dating another trans-person is that we tend to collectively be a depressive lot, so there could be some possibility of feeding off each other's negativity.