This popular frontend gets an update now, since I tend to not use frontend's much lets move swiftly to the news which this time is a bit lighter than usual:

Fixed
• Menu theme, font color of selected item was not being applied
• Snapshots not always displayed after image panel was set empty
• Scan for missing icons was not running games in some view modes
• Games list not being correctly sorted (left panel editor)
• Access violations in scan missing/not used icons/images
  
  Changed
• Scan for not used images. Only files that are not used by any games are removed
  
  Added
• New setting: "Auto Rename Snapshots to Old Format" / "Delete Files After Rename" (preferences, "Images" / "Categories" tab). This will automatically rename snaps from new MAME format "\gamename\0000.png" to the old format used by the front-end "full_gamename0000.png". Click on the "help" button next to its checkbox for a more detailed info... disabled by default

Download from the homepage.