Yeah i have seen that "upgrade for free if you bought something in the past thing'. Theres a time limit that Apple sets for that kind of thing one site describes it this way "If you buy once leopard's actual release date has been announced but before that date arrives, you'll get an upgrade coupon for leopard. If you buy before the release date is announced, you pay full price for the update. At least, that's how apple's done it in the past.

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"What you hear in a great jazz band is the sound of democracy. “The jazz band works best when participation is shaped by intelligent communication.”
Harmony happens whenever different parts get to form a whole by means of congruity, concord, symetry, consistency, conformity, correspondence, agreement, accord, unity, consonance…….