Many distros are beginning to include qtparted in their installers to allow for NTFS resizing. I think this would be a great addition to help get windows users to use linux since there would be no side-effects.
a) qtparted brings in a whole new set of toolkits, languages, etc into the installer which isn't feasible. b) adding ntfs resizing support can't be done for the same reasons as why we can't ship the NTFS module in a kernel.