Warning: The selected master page has no approved version. This site may appear to be broken to users without the view versions right in the Master Page Gallery.

This is a simple fix for a strange problem that I didn't expect.  I was going to apply a new masterpage to a site and some subsites when this lovely red message came up:

Warning: The selected master page has no approved version. This site may appear to be broken to users without the view versions right in the Master Page Gallery.

As that was something that I didn't want to risk I ended up deleting and readding the page to the masterpage gallery.  I also found these directions if you're looking for a fool proof method:

Click Site Actions –> Site Settings –> Modify All Site Settings
Click Master pages and page layouts
Click the down arrow next to your .master file
If Check In is an option, click Check In
Click OK
Click the down arrow next to your .master file again
Click Publish a Major Version
Click OK
Click the Down arrow next to your .master file
Click Approve/reject
Click the Radial Button next to Approved.
Click OK.

Check your page out again.
If that did not work, click the down arrow next to your .master file for the fourth time.
Click Manage Permissions
Make sure that Portal Members have Read rights.
If they do not, Click New –> Add Users

Type Portal Members in the Users Section
Click OK
Click Read in the Give Permission Section.
Click OK.
This should address both permission issues and approved version issues.

http://thenewpaperclip.com/2007/02/10/create-a-master-page-in-microsoft-office-sharepoint-designer-2007/