I didn't read the majority opinion yet. I have to bill some time today. But if a legitimate public purpose with a public benefit is involved, as found by a court, then yes, the power of condemnation should attend. This picking and choosing between public purposes doesn't do much for me. I described those public benefits that could attend this case. I think they are substantial, or could be.
But Justice O'Connor's position is that the public purpose must be to remedy an affirmative public harm, and not merely to substitute some more desirable benefit.
The real problem here is the incorporation of the Constitution. The Founding Fathers never envisioned the Constitution applied to this scenario in any way at all, and so they didn't phrase it accordingly.