Icons remains the same after I have changed the default program for opening the file
You can try to rebuild LaunchServices database from Terminal:


  /System/Library/Frameworks/ApplicationServices.framework/Frameworks/LaunchServices.framework/Support/lsregister
  -kill -r -domain local -domain system -domain user


Path to lsregister on Mavericks is:


  /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister