I only have 8 gb of music.... The only reason I ever touched a Mac was to learn iphone development. Let me run OSX in a VM in Windows, and my laptop would be a macbook pro (i like the metal, better heat displacement, now if only I could get a windows logo to put over the led backlit apple on the cover...), with windows 7/8 and a VM of Lion for iphone dev. (Better yet let me do it on Windows, but that would mean that apple would lose hardware sales to run their OS, and dev environment for iOS. it is a good sales move to bind the two.)
The reason the memory management is the way it is on Windows comes back to the methodology. E.g.
Application Start, Import all files in directory to a database and delete the files, upon completion wait for another file to be placed in directory.
In Windows land the RAM allocation happens during the import, but as soon as the program says it no longer needs it, its zeroed and back to the pool, which is great because then another application can use it without going through the motion of can i have ram, yes you can have this much please wait a second so i can release this inactive stuff.
In OSX land, the OS thinks that the application may need that RAM space again so it would keep it in inactive state most likely, when the truth is that the program just doesn't need it anymore. That's why programs will load noticeably faster under OSX, because it basically left itself still available in the RAM.
Edit: I take it that you haven't read much about SuperFetch and the fact that the exact same complaints in this thread about Mac OSX have been made about Windows 7?
Adobe used this concept and built the speed launcher which basically loads some of adobe reader on windows start up instead of when you actually open a pdf.
Some developers might call the existence of RAM left allocated after an application is closed a memory leak... (at least in Windows... it would only be a leak in OSX if it is still active, but you get the joke.

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