To get the sounds, use the link I sent you:
http://www.beingmanan.com/wp/2009/04/windows-98-plus-themes-for-windows-7/
Also, Windows 7 comes with over a dozen sound packs, even before downloading your own (for example, the Halo theme on their site has sounds from the game). This is considerably more sounds than the precisely 3 sound packs that were included with Windows Me, 2000, and XP, so I'd say they're improving.
As always, Microsoft provides the platform or the structure, but they do not provide content. It is up to other developers or creators to build upon that scaffolding.
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