Safari and Chrome both share this issue. Basically if you copy and paste data from a textarea that has been tab delimited, it fails to format properly in a spreadsheet like Excel. It appears the tabs get changed to spaces.
You can see the behavior while using this site: http://www.batchgeocode.com (copy and paste from the first field)
IE and Firefox don't have this problem. I have noticed this has been an issue for quite some time.