i think it really depends upon the situation.
i'm fully involved in my children's lives, and they live with me full-time. if someone were to refer to me as "biomom" rather than just mom, yes...i might be bothered.
however, i was also a step-parent that made a deal with my daughter's biological mother...she'd give me her kid and i'd continue to pay child support until she was eighteen. she readily agreed, and i received the most life-changing relationship of my life. that child IS mine, period...just ask her. when her father and i split ten years ago, she stayed with me. she's now 26, and i was just the labor coach for her second child (just as i was with her first) and once again cut the cord...while the other parents in her life didn't even know she was expecting.
it's been an emotional evening. i could see where any involved parent would be upset with the idea that someone else was trying to take over their role. however, if they aren't filling it, it's a whole 'nuther story.
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