You can get items that do not have an alignment choice attached to them through crafting, quest rewards, and such. So in no way are you forced into an alignment. As a Sith you can even make light side choices and vice versa for a Jedi.
I've been testing the game for about a month and I've never felt forced into a particular alignment. I won't say any more...NDA and all that, but take that for what its worth.
"You'll find that many of the truths we cling to depend greatly on our own point of view."