Early builds of Windows 8 have been going out to ODM and OEM partners this week and details are already leaking out of the cracks. Judging by some of the rumors it looks as though Microsoft might go down the Apple path and have a feature that is similar to Time Machine.
Microsoft seem to be calling this feature "History Fault", with the description of the feature explaining:
History Vault helps protect your files against accidents that could cause data loss. If an external disk or network attached storage is used, it can even protect your files against disk or entire PC failure.
This would be a great feature as it has the ability to restore to a specific time or date on the system. Users will also have the ability to select files that have been previously edited or deleted and restore them to previous versions with different timestamps.