Some, especially her husband, state that this is what she would have wanted. Others disagree. My view on this is that where there is a shadow of a doubt, choose the choice with the least potential for harm/error - In this case it is obvious to me that the more grave error, if indeed it is an error, is to allow her to die.
They seem to be basing her "choice" upon random comments she made over time in relation to a television program where she supposedly said something to the extent of "pull the plug on me! No tubes for me!" Random comments made when a situation is completely removed from oneself do not to me seem to be something to base a life or death decision upon - if she did indeed make such comments.
Most claim her condition to be hopeless and the theory on stopping the feeding is to "allow her to die with dignity" or something like that. Well, first off, if shes been in this condition for years, the dignity largely already went by the wayside - at least of the type that I believe many consider in this - the ability to care for oneself, privacy, etc.
Now granted, it is indeed likely that by today's standards, her condition is indeed hopeless - but given the proper nutrition, her body has still been sustaining itself thus proving there is sufficient brain activity for life. At this point in time it may well be not the kind of life many people might call a "quality" life and she is likely lacking some degree of that elusive aspect called "quality of life" but the fact remains is that we don't know. We don't know where her mind/brain is and/or has been all this time. We do not know where her mind and spirit are dancing today. We do not have any way to know what this woman's personal experience is or what it has been.
Her parents claim she responds to them. In the few photographs that I have seen, she is smiling. That tells me that there is still some degree of emotional life going on within this woman. For all we know, she may indeed have a complete and full emotional life going on inside of her and it may be only its expression that is blocked by her current condition.
Hopeless - by todays standards - may not be hopeless by tomorrow's standards. We do not know where our medical technology may go in the next decades. There is currently much work on medical nanotechnology which I believe will one day be capable of repairing even individual brain cells. Without allowing her life to continue, there is no chance Terry Schiavo will ever be one to benefit from this technology.
I do believe in the preservation of life wherever possible. My only real exceptions to this are where to preserve the life as is could or would be likely to result in more damage to the being or where the quality of life is such that the individual is wracked with pain and/or severe discomfort constantly. Nothing that I have read indicates that either of these apply in Terry Schiavo's case.
I do hope that at least someone in charge of this woman's well being has the consideration or tenacity to at least attempt to preserve what is left of her life via cryonics if indeed this case continues in the direction that now seems certain. One simply does not know what future technology may bring.