Spreadsheet Page Blog
Office 2013 RIBBON TABS
During the Office 2013 preview, one of the complaints was about the UPPER CASE text in the tabs. For example, see this thread.
Apparently, Microsoft employees read their forums. In the final release, you can change the case of the Ribbon tab. Just go to the Customize Ribbon section of the Excel Options dialog box. Select a tab name and click Rename. Type your new name, using any mix of upper and lower case character. But… If the name is the same as the original tab name, it will revert to uppercase.
The trick: Just add a space character to the end of the name. Here's an example. The HOME tab has been renamed Home<space>.