Its been stated that it will be remade using the Unreal 3 engine. This means it isn't just a mere swap of tectures, but an actually proper REMAKE. And it isn't just the textures they're replacing. Lighting, meshes and character models are all being reworked. There's also a new save system, so a lot of new code lies inside this remake. There's also a new interface, though UIs are easily changeable anyhow. And Timmins mentioned that they will be adding more content, besides the "The Lost Chapters" expansion, and usually when you do that for a remake, you would redo the code so that its easier for you to just add new stuff with less possible conflicts.
Now, whether they would add that option to play as either a male or a female is completely debatable. I personally think they won't, as that would mean rewriting a lot of the original script and getting some of the old voice actors to come back a say "girl" instead of "boy". Also, I feel that so many of us are used to the lore of a male Hero of Oakvale that having a possible female Hero of Oakvale just feels weird. Moreover, that's just more work Lionhead might not want to invest in.
Still, anything in possible. The one thing they've done better with this than with any other Fable is that they haven't promised much. So we may be pleasantly surprised. Or not.