If you are getting MyTopo maps that look like this, you should download the new version, out in beta form now.
http://topofusion.com/beta.php(for registered users)
Other additions/fixes/etc:
4.3 [10/13/11] (Beta)
Fixed corrupt myTopo maps due to server change (chunked responses)
Added ability to read .KMZ files (zipped .kml)
Added new unit type "Nautical" for nautical miles and knots
Added ability to expire all maps for OSM, Open Cycle, Mapquest, Open Aerial and
myTopo maps (Options->Preferences->Tilesets)
Improved accuracy/detail when adding elevation data to tracks
Changed encoding of all xml files (GPX, KML, etc) to ISO-8859-1 from UTF-8 to
allow special characters
Fixed error 380 with Garmin Astro Live Tracking
Fixed "place waypoint" button on Goto form to copy both coordinates