At this point, as callous as it feels to say it, there's not much left to do but wait for her to die.
A commentor on this blog this weekend took umbrage with my labeling Michael Schiavo as "evil." The label is not just about his views on euthanasia. It also has to do with forsaking his wedding vows ("in sickness and in health"), refusing to allow her to have any therapy, refusing to allow further medical studies on her condition, "remembering" that Terri expressed her wishes about these matters only years after Terri entered this state and after he had won his malpractice suit, being content to starve another human being to death, and his castigating anyone who disagrees with his decision.
The commenter--a medical student--also provided medical information about PVS. But whether or not she is truly in a PVS is under dispute. (See, for example, this affidavit by Dr. William Cheshire.)
Finally, the suggestion has been made that the "Christian right" is being used here by the Republicans. I disagree. First, it was the "Christian right" (among others) who persuaded Congress to act--not vice versa. Second, moral revulsion on this issue does not belong to the right alone. For example, this weekend Jesse Jackson and Ralph Nader both expressed their disgust with the way in which Mrs. Schiavo is being killed. In Congress, Tom Harkin (D, Iowa)--a liberal's liberal--was at the forefront of passing the (ignored) legislation.
For further response to the "cynical political ploy" view, see Michael Barone's latest column.
Al Mohler's blog entry today, Terri Schiavo--The Bell Tolls for Humanity, provides a helpful recap of the case and the ethical-legal-medical issues involved.