Writing tip of the day: if you give your characters gender-neutral names (or names that have masculine and feminine forms that are easily confused, like Rene and Renee), make sure that you give your reader some means of identifying the gender of the character early. Unless the ambiguity is intentional, this can really trip up readers.
What I had against me: the story is told in the first person, so there’s little opportunity for physical description that doesn’t seem intrusive; the story is set in a post-Singularity world, so physical descriptions are out in any event.
It’s also interesting how important a role gender plays in our ability to sink into a narrative. Uncertainty about the gender of a character is like a toothache, constantly pulling the reader out of the story. It does raise interesting questions about how gender identity will be handled in the post-Singularity world.