^^ key word "up to" $500, you can get home premium OEM for $140. and other versions for $100.
cost isn't a reason to pirate, it is a lame excuse cause you don't "need" Ultimate edition, or "need" vista, OS X most "advance" OS, give me a break, most of what OS X is it got from past OS's already in the *nix and windows world. (yes i know ms has gotten it's idea's from the *nix world as well, they are all guilty of stealing others ideas)
OS leopard is pirated period, just open your eyes a little, but since their market share is a fraction, the damage done isnt near as bad as MS nor is it heard of as often,, in fact pirating software for MAC is almost easier as you can simply copy an entire directory from one system to another, no copy protection, or very little to get around, did you not hear of the various kids walking into stores with ipod and usb drives copying software from MAC's... cant do that in windows, you need the disks. (the registry sucks, but it makes this type of piracy harder)
If apple wasn't a "hardware" company first, they would make it more complex if you could install the OS on any hardware, which you now don't need a MAC to do so since now they are using hardware pc's have for years, you can buy specific hardware off the shelf and build your own mac more or less now, and if that trend continues, dont think for a second Apple wont make it more complex for you, cause when people pirate, things are never hard for them, it just makes it worse for the legit people.