In IE9, there is an extra partial button in My Workspace: Worksite Setup if the user checks the box in front of My Workspace, which when clicked, attempts to delete the site. Luckily, My Workspace cannot be removed.

To reproduce:
In IE9, log into My Workspace and click on Worksite Setup
Check the box in front of My Workspace - notice the extra partial button beside "Delete" at the top of the page
Uncheck the box for My Workspace - the partial button disappears

Tested clicking the partial button as another user in IE9. Checking a site you do have the option to delete, will ask you to confirm removal.