I'm sorry but the Plant/Allison Krause thing is just awful imo. At least the one song I've heard. I've talked to other people who feel the same way. Even worse than being bad,it's just dull.
As for a Zep tour. Plant is just setting himself up for years more of the same questions by doing the one off show. I don't buy the fact that he just wants the band to be remembered with one final good show. He could just stand by the upcoming releases if he wanted to do that.

"It's just some friends of mine and they're busting down the door"