I have updated the “Hide List and Library Column Headings” article to add notes for SharePoint 2010 and Office 365!
Go here for the details: http://techtrainingnotes.blogspot.com/2009/06/sharepoint-hide-list-and-library-column.html
Note: after this customization the checkbox column disappears, at least until you mouse over a document. Bug? I think it’s a bonus!