Looks like there might be a show stopping bug in Windows 7 RTM. A memory leak has been discovered in the chkdsk process when using the /r command to scan a non-system disk.
The issue does not appear until stage 4 is reached, at that point the memory leak will cause all of the ram in the system to be used.
This can cause the system to become non-responsive and even cause a BSOD in some cases. This issue also seems to be present in the Server 2008 R2 RTM as well. A patch is expected to be released in the same manner as the mp3 bug that was present in the Windows 7 Beta release.