When creating a new partition (or formatting an existing one), please provide an option to overwrite unallocated space (or existing partition) with zeros. This would allow for a relatively quick way of overwriting all the underlying sectors on the disc, and thus ensuring (more or less) that lost data cannot be recovered. In the post-Snowden world, this is more and more a necessity for users. 

For example, Gnome's Disk Utility ('gnome-disk-utility') allows two 'Erase' options when creating new partitions (see attached screenshot): 
- Don't overwrite existing data (Quick)
- Overwrite existing data with zeros (Slow)

The first option is, I suspect, what GParted is currently doing. That is, nothing: erase file system, create new one, and move along. 

The 2nd option is what I'm suggesting should be available to users in GParted.