Just to throw in my two cents on some of the topics being discussed...
1.) I think whether or not the tour is Equity or non-Equity is anyone's guess. Most of the original cast were hired as non-Equity and then got their card when the show transferred to Broadway. The creative team could possibly just be looking for really fresh talent, hence going non-Equity for casting. That said, I don't really see any reason for the tour to be Equity. HAIR is a pretty simple show with little to no effects/elaborate sets, so I don't think there would be any differences between the tour and Broadway.
2.) The whole West End transfer has puzzled me from the beginning and I agree with dramamama that it doesn't seem likely that members of the cast with ties to the city would leave for 6 months or however long the transfer is planned.
3.) In regard to the fate of the Broadway production, the absolute earliest I could see it possibly closing is after Labor Day 2010. Now this is all dependent on the nut (which nobody knows for sure), but I'm fairly sure that even with their slipping numbers that they are still exceeding or at least meeting their operating costs. As mentioned, the show has recouped, so anything over the nut is profit. I feel that the producers really believe in the show and even if HAIR slips below their nut for a few weeks during the dead winter months, I think they would still keep it open.
Wicked Tour (2/26/08); Wicked Bway (7/1/08); HAIR (7/1/09); Rock of Ages (7/2/09); Wicked Bway (7/3/09); Mary Poppins Tour (8/2/09); Wicked Tour (11/18/09); Wicked Tour (12/5/09)