No, I don't think so.
Genetic engineering is a slippery slope. Sure, we could get rid of some horrible diseases. But we could shoot ourselves in the foot, so to speak, if we all decide upon the same genetic characteristics. If we could select physical characteristics, wouldn't we all tend toward the same? And if our genes became similar, because we all designed them to give us this trait and that, immunity to this disease and that, we would lose the diversity of our gene pool. We could not keep up with all of the quick mutations of disease and our lack of natural heartiness would probably be our undoing. If one strain of the flu erupted, for instance, that we didn't have immunity to, it would wipe out far more people than it otherwise might. It might not wipe out everyone but it's like Russian Roulette. We would be gambling--assuming we know now what qualities are best for the survival of human beings, which is fairly unpredictable, instead of letting natural selection do the choosing (I know you could argue now that we don't allow natural selection to do enough choosing because of the advancement of medicine allowing so many to survive and reproduce who otherwise would not.)
So the notion that we would create different subspecies, I think, is the opposite of what would happen. I think people would tend toward being simlar--stong, beautiful and healthy. And of course the first two vary somewhat, what makes someone "attractive"--a symmetrical face, proportional features--is the same all over the world by and in large. And if "types" emerged, it would be the result of people coming up with genetic "plans"--people making recommendations on how to engineer and what to aim for. The whole genetic picture would have to be carefully planned out. Things have to work in unison--you could give someone the ability to shed lactic acid from his/her large muscles quickly, a very strong and light skeletal frame, but if the heart is not also carefully engineered to withstand the physical endurance level of the person, the exertion on the heart from the person's "superabilities" might end up being that person's death. That alone makes the whole notion of performance based genetic engineering completely unethical--experimenting on human beings would be inevitable, and could not possibly be done with consent, as these are decisions made before the child is born.
Well what I personally would do would be to make myself about 10 feet tall, right? And then have the subordinate worker class, people standing at about 6"3 or so, be the people to serve me. Most women I would design to be about 8 and a half feet tall so that they would feel physically inferior to me, the almighty one commanded by God to rule the world... While they would simultaneously feel SUPERIOR to the pathetic working class who are like 2 feet shorter than them. This way I would get all of the vagina, and everyone would be so stupid and oblivious as to how simple my system is that they would just mindlessly abide by it!
bwahahaahaaaaaaaaaaaaaaaa
ha?? But wait! What if there was another person that came along from another planet that had a bigger one than me? Well... Obviously I would declare war on this lifeform for all of eternity!
I think it's unlikely. Speciation requires separation of populations for many generations. It's unlikely that genetic engineers would deliberately make extensive modifications to the genome that would make differently modified humans unable to breed with the bulk of human population, so they would be continually breeding the modified genes into the general population.