Just saw this tidbit over on ZDnet. Seems if you use a Guest account then try to log back into your user account you can end up losing all the data in the user account. Since I don't run SL I didn't read closer, here's the link to the story:
Snow Leopard bug deletes all user data (Updated) | The Apple Core | ZDNet.com
Mini1: Vostro A90, Black, 2G, 1.3 Webcam, Bluetooth, 64G SuperTalent, OS X 10.6.4
Mini2: Mini9, Black, 2G, 0.3 Webcam, Bluetooth, 32G RunCore, OS X/Win 7,
internal PCI-e SHDC Reader
Mini3: Mini10v. Black, 2G, Webcam, 640G HD, OS X 10.5.8/Win 7/Ubuntu [Hibernate w/NBI 0.8.3 RC4]
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