Earlier generations of Windows have offered parental controls to track younger users, but much of the emphasis has been on filtering out inappropriate content, which is always a precarious business. Windows 8 will take a different approach, sending a weekly email report to parents telling them what their kids have been up to.
Microsoft's Building Windows 8 blog outlines the changes to the Parental Controls feature. Rather than having to create a lot of settings when an account for a child is created, parents can simply select the Family Safety option on the account set-up screen.
They will then automatically receive a report (click on the top pic for a larger version) which summarises which apps and sites have been used most often, complete with links to set up filtering or time limits if you want those options. The time limit options, which previously were restricted to setting a "bedtime" for the account, can also now be set to a fixed number of hours per day.
As you can see above, these features aren't in the current Consumer Preview version of Windows 8, but will be added to the release preview which is expected between now and when Windows 8 is commercially available. That's widely predicted to be before the end of the year, though we don't yet have pricing. I'll be curious to see if the filtering options only work in Internet Explorer.
Keeping your family safer with Windows 8 [Building Windows 8]