Reading the posts in this thread, I can't help but notice an awful lot of assumption. We're assuming that consciousness transfer, even if it became scientifically possible, would theoretically send the you that you are into this new body. To everyone around you, your personality, your memories, everything that made you "you" is in this new body, but how can they really know that "you" made it into this new body?
What I mean is...well, I don't know what I mean. I remember as a kid thinking about how my consciousness is unique. I can't see my own face without a mirror, in a sense my consciousness is "trapped" within this body, and cannot be shared to other bodies. Even if I had a brother, and we lived the same lives, looked and dressed exactly alike, and even thought the same things, we'd still have two completely different consciousnesses, and although we could look at each other, we couldn't look at "ourselves," if you catch my drift.
Although it technically isn't, I feel like this "Twin" scenario would be the same as a "Cloned-Consciousness" scenario. In other words, your memories, knowledge and experiences get transferred into this new body, and this new "you" continues to live your life, but the "you" that died, the "you" that was looking out from your "original" eyes, experienced things with your "original" senses, would not transfer over. To put it more bluntly, your memories and experiences get transferred, but the soul does not.
Of course, this is all skepticism, as science has yet to determine the nature of the soul. I'm sure if consciousness transfer came into existence, few would really care. As I said, if we're assuming that consciousness transfer is "perfect," then no one on the outside would really be able to tell that you were a different "soul." Then again, maybe it really would send your "soul" into the new body as well, and you'd continue your life as though nothing had happened.