Chiraque:
"I was wondering what ya'lls thoughts were on the mechanization of humans through "enhancement prosthetics" (prosthetics designed to replace organic body parts with superior mechanical counterparts)"
Being a big Science Fiction fan, I read in "Ghost in the Shell" a very important thing about cybernetics: If you do not go full cybernetics, you essentially are wasting your time. For even if one arm were to have super strength, for instance, you would not be able to support the weight it could carry, without crushing your shoulder or ripping it out of the socket. Similarly, with organs, if they were too hard on the body, despite being far better, they'd be worthless.
"and "mind uploading" (the replacement of a human brain with a mechanical counterpart and/or the copying of that brain)."
If the human brains is replaced without the uploading of the mind into it, then that human ceases to exist. The human being is defined as his mind.
"Where is this field at right now?"
Infancy and will probably not create anything of worth. I do not foresee cyborgs are as a viable field beyond prosthetic replacements.
"Do you believe mind uploading to be possible?"
Unless the means whereby neurobiological signals can translate into a subjective experience within the Cartesian Theatre can be replicated flawlessly and bring with it every ounce of memory and personality of that person from beforehand, this process could not be done. Considering that there is nothing in the biological signals that explains the summoning up of certain images in one's mind when one directs one's thoughts towards that, nor the creation of a self from the mind, and various other such things. I view "mind uploading" as completely impossible.
"How does the concept of the ghost or soul/spirit in the human machine play into this? "
It would actually be much easier to do such things, if we could find, extract, and implant a soul - which would have everything with it, presumably - of someone into something else.
"Can one be completely mechanical and still be human"
If you were human before and retain your mind, yes. If not, no.